Deep IR conversion on D800; AR filter + many questions

Strangely there's no "Infra Red" forum, so, I guess, I'm posting here.

So, basically, I've dabbled with the IR in the past, right around 2006. It was the simplest of setups: my old D70s + a Cokin plastic IR filter. Needless to say, I didn't get very far with it, mostly because focusing was next to impossible. Not being very serious about the thing, I had to give up IR. But now that I have a "spare" D800 just laying around, collecting dust, I thought I'd put it to good use.

I like to think that I'm quite knowledgeable in the field of IR photography (even considered getting into it in the days of film), however, my personal experience with it is very limited. When it comes to making "artsy" photos I consider myself somewhat of a purist, so, all that "false color" stuff is just not for me. I'll be shooting in a desert environment where there are lotsa rocks, mountains, canyons and hardly any vegetation, which is a good thing because I'm not crazy about the "white trees". I'm all about dramatic B&W tonality and strong contrast between the rocks, the clouds and the black sky, not weird-looking aspens. So, I want the maximum possible effect on the sky and I really do not want to fumble with any filters on the lens. Naturally, I need to install a ~830 nm filter at the sensor.

I was able to find and investigate 2 possible routes I could go: Lifepixel and Kolari Vision.

First of all, how sharp is a filter like that anyway? I think both of them claim "German glass" but what does that translate to in terms of image sharpness, granted that "deep infra red" requires some serious "filtration".

At Kolari Vision, in addition to the "Industry-standard", they also offer 2 "coated" versions of the same filter (which is rated at 850 nm, as opposed to 830 nm, btw). I am somewhat concerned about the hot spots, especially that there's no information regarding the 2 lenses that I plan to be shooting with. How effective would be that kind of coating against IR hot spots, if at all? I mean, it is a hundred bucks extra but if paying it means saving even a couple of, otherwise ruined, gorgeous "keepers" then I'm all for it. Again, does that "coating" affect the image sharpness in a negative way?

My current go-to lenses for any outdoor excursions are the Tamron 24-70/2.8 G2 and the Tamron 70-200/2.8 G2. Sadly, no hot spot data on any of them but maybe someone will care to chime in.

And lastly, the Auto-Focus. I'm familiar with the problem all too well. Luckily, we live in the age of Live View photography. Needless to say, I'll be focusing exclusively via LV, so I should be fine. Am I right or am I missing something? Because at LifePixel they make you choose the type of AF calibration even for Live View. It says "Universal (For Live View cameras). Are they even doing anything to the AF system or is that option there to simply tell them to leave it alone?

So, there. What do you think?

With the exception of rather long exposures you should have got good results from the D70 (it has a weak hot mirror, so is reasonably sensitive to IR) the biggest problem perhaps being focus shift. I used a Pentax K100d for IR which is fairly similar & had no issues as long as I focused manually with lenses with an IR focusing mark.

These days I tend to do quite a bit of the false colour stuff you don't like. I only use mirrorless cameras for IR now as that gives me liveview in the viewfinder. Focus with these is done just the same as in visual light. LV should be similar, most cameras use contrast based focus in LV though a few have phase detect built into the main sensor. with both of these I believe there's no issue with AF shift.

I've no experience of the AR coated conversions but the reviews I've seen do look promising.

Deep IR should be sharper than standard IR (720nm) but will be noticeably less sensitive - probably over a stop. A few of my lenses have a significant drop in transmission above 800nm. In the desert IR should be plentiful so I doubt either will be an issue.

This'll be of limited use, but...

I have a D90 with a 690nm low-pass conversion (which gives a little colour) - my choice of D90 was to be the cheapest option with live view. I have some longer wavelength IR lens filters that I can use if needed, and there's certainly a drop-off in sensitivity as the wavelengths get deeper. It's been nothing like as bad as when I shot my unmodified dSLRs with an R72 on them, though - I think the D700 managed live view, just, but my D8x0 bodies have been shooting pretty much blind and doing 30 second exposures. I'm not sure how much adjustment to the AF system may have been done; I get fairly good AF hits, but then 12MP and a strong AA filter isn't so demanding, and I'm not usually shooting wide open.

It sounds like you're interested in more than the cheapest option, so I'll defer expertise to others. But I can vouch that I've had a 24-70 Tamron G1 (same optics, I believe, as the G2) working okay. I wouldn't like to guarantee absolutely no hot spot, but it's not something that's been bothering me. I often end up using my 14-24 to compensate for the DX crop, though, or a 28-80 just to keep the system small; the latter probably isn't helping my sharpness measures. But it's not like the old HIE missing anti-halation glow.

Good luck.

I think you will get the same results, except you are mangling a much better (and costly) camera. Send me yours and I'll send you my D7000. Mangle away!

* Seriously, you *have* to manual focus.

* There is nothing wrong with the Coken IR filter; I have one. It works well.

* You should stick with primes, and limit yourself to using only one lens. In time you will know how much to change your focus.

* Use DOF to nail your focus.....just light you were taught.....

The photography is not any different, you just got busted on everything your camera probably did for you.

My technique.....

Remove IR filter

focus

put IR filter back on.

Meter with an external light meter with the lowest ISO possible

compensate 4 stops

Shoot at least F8...F16 is better. Compensate by the shutter. Do not bring up ISO, as you will lose detail.

Don't judge by the viewfinder. Wait until you open up the file.

I wish there was an EVF in my D800 but it is what it is and it is what I have available. Having electronic shutter wouldn't be bad either. If I keep doing IR, I'll most likely dedicate a mirrorless body to it in the future.

In the meantime, I'll be using the OVF for composition and the LCD for acquiring and confirming focus and checking the histograms... somehow. Please do no recommend me any weird gadgets that go over the LCD, I know all about it.

Andrew, I've seen the data on the first generation 24-70 myself but assuming that the G2 is "also fine" based solely on that would be very foolish of me. It's all about what type of "paint" they chose to use and NOT whether they kept the original optical formula. I know you know this and I'm merely illustrating a point to everyone else that there has to be solid "data" to know something like that to a certainty.

So, not much help really so far but, people, do keep chiming in. In the meantime I think I'll email Lifepixel and ask them if they have any AR coating on their 830nm filter.

And, Peter, thanks but no, to all of it.

I've converted a D50, 4 x Nikon J1s and 2 J5s, a D90 and my current fav. a D600.

These are all bare conversions. ie filter stack all gone and replaced with a piece of un AR coated 'plane' glass. In my case ~1.7mm lets me keep infinity focus.

Most of my stuff is not landscape, it's more forensic, fine art, document stuff & textiles up to about 5 x 4 meters in size.

My current IR lens is a Sigma 135mm 1.8. The only downside is the big 82mm filters. If I need wider, it's either a Sigma 35 or 50mm ART.

I'm usually using around f2.8/4 as DoF is not an issue and AF focusing in LV is spot on.

Some people have hot-spots with their 50mm ART. For reasons unknown I don't. Maybe I would at f16?

All composition and focusing is done on the back screen or a laptop screen by tethering.

Zoomed LV using AF works perfectly well. Camera VF is black, but that's not an issue for my workflow.

Metering is a bit trial and error. Take a few and check the histogram (they are based on JPEGs even if you shoot only RAW) and learn how far you can push it.

I have a full set of IR trans filters. 690nm > 1050nm for IR.

Hot spot generation is very camera-body/lens specific. It may even be wavelength specific.

I use big IR LEDS for my work, usually 940nm of around 30-50W.

Different from landscape work, but hopefully of some help.....:)

Agreed, David - I wouldn't like you to commit to anything based on my limited experiments. Although presumably you'll find out yourself if you've already got the lens! Bjorn's naturfotograf site discusses IR compatibility, although not for recent lenses. Given that you're adapting a preexisting camera, despite the D800's slightly odd line skipping live view, I'd expect it to be basically fine (and capable of slow autofocus) - much as I like the finder view, nothing stops a moderately modern dSLR from being used like a mirrorless one if you want to, you just don't have PDoS autofocus speed. Even my D90 was basically fine as a live view camera with the long wavelength IR filters over the lens. But without pushing my luck with depth of field, my D90's phase-detect autofocus is just fine - but I don't know whether it was adapted, and how.

Good luck with it.

Some people have hot-spots with their 50mm ART. For reasons unknown I don't. Maybe I would at f16?

There are a VERY wide range of factors involved in hot spots.

Aperture certainly can be a factor.

I've had hot spots at all f-stops using a lens on one (non converted body) but with the same lens never any on my converted body.

Other times just turning round & shooting the opposite way (into the sun) has introduced a hot spot

Then I've seen bad hot spots when shooting close-ups, but not at normal/infinity (without adding extension tubes etc) both these within minutes same hardware and at similar orientation to the sun.

I think you will get the same results, except you are mangling a much better (and costly) camera. Send me yours and I'll send you my D7000. Mangle away!

 

* Seriously, you *have* to manual focus.

* There is nothing wrong with the Coken IR filter; I have one. It works well.

* You should stick with primes, and limit yourself to using only one lens. In time you will know how much to change your focus.

* Use DOF to nail your focus.....just light you were taught.....

 

The photography is not any different, you just got busted on everything your camera probably did for you.

Thank heavens none of that applies to mirrorless cameras!

I'd guess I've used between 10 & 20 lenses on my converted body. Three of them AF with no issues, the others are mainly adapted lenses so no chance of AF. Two of the AF lenses are zooms.

Even with my DSLR I had no issues using multiple lenses, simply focus using visual light, add the filter & shift the focusing ring to the IR mark. BINGO!

If your lens doesn't have an IR mark it's generally not too difficult to add one (a pen mark on a bit of tape).

wrt Cokin filters I've never used one for IR but I've found light leaks (round the back of the filter between it & the holder) to be a serious issue with dark ND filters & would expect the same with IR unless special care is taken to block them.

FWIW my pre-converted MFT body cost less than getting a conversion for my old DSLR at least until you add in the optional EVF I brought 6 months later.

I guess as manufacturers have installed even stronger UV and IR blockers over the sensor there's no need to ensure the black lens 'linings' are not huge IR bouncers and any AR coatings actually 'work' over 760nm

As conventional film was IR insensitive who cared about IR hot-spots!

Considering how many/few people shot IR film, it's amazing that nearly all Nikon's (and others) MF lenses had an IR offset mark... and of course what wavelength are they offset for? Kodak HIE is labelled for up to 900nm.

De-filterstacked DSLRs get to about 1100nm and then sensitivity falls gracefully away.

Considering how many/few people shot IR film, it's amazing that nearly all Nikon's (and others) MF lenses had an IR offset mark... and of course what wavelength are they offset for? Kodak HIE is labelled for up to 900nm.

 

De-filterstacked DSLRs get to about 1100nm and then sensitivity falls gracefully away.

Film IR was unusual but not all that rare - I've had a few people comment (on seeing my IR shots at club exhibitions) that they'd shot some IR on film. I guess adding the mark would have been a fairly inexpensive extra :)

Most film IR shooters would probably have used a R72 or equivalent which typically starts transmitting about 700nm & reaches max transmission around 740nm. So I'd expect the IR mark to correspond to something around 800nm.

The insensitivity of film to IR was also a factor in trying to shoot UV. All the old UV pass filters leak considerably in NIR, making them unsuitable for UV on converted cameras. There are now some specially coated UV pass filters available, but they cost more than my last camera, and that's without getting the special lenses!

There are now some specially coated UV pass filters available, but they cost more than my last camera

That's the great thing about using UV LEDs, they emit zero IR! If you're working in a dark room you don't even need any filters at-all*!!

I am the proud (and now poor!) owner of a 2" Baader Venus filter....:cool:

* You do need a couple of UV trans filters on the 30W UV LEDs though, as they do emit some visible violet/blue up to about 425nm. Try putting..

"ZWB2 1.9mm Ultraviolet UV Band Pass Filter" into ebay search box. 42mm diameter for ~ $2. I stack 2 per LED.

Agreed, David - I wouldn't like you to commit to anything based on my limited experiments. Although presumably you'll find out yourself if you've already got the lens! Bjorn's naturfotograf site discusses IR compatibility, although not for recent lenses. Given that you're adapting a preexisting camera, despite the D800's slightly odd line skipping live view, I'd expect it to be basically fine (and capable of slow autofocus) - much as I like the finder view, nothing stops a moderately modern dSLR from being used like a mirrorless one if you want to, you just don't have PDoS autofocus speed. Even my D90 was basically fine as a live view camera with the long wavelength IR filters over the lens. But without pushing my luck with depth of field, my D90's phase-detect autofocus is just fine - but I don't know whether it was adapted, and how.

 

Good luck with it.

Yes, I already have the lens but there is something that I (supposedly) do have some degree of control over.

I'm am still talking about the Anti-Reflective coating on the in-camera filter. Judging by the number of responses on the subject, which is zero, I'd say that it is a very uncommon feature to have. I myself, have only just found out about it, whilst shopping around for an IR conversion. I was like, "Wait, something actually CAN be done about the hot spots??????". I dunno..., nobody's saying anything...

What I'm trying to find out is, first of all, if such anti-reflective coating helps at all with stray IR light or is it just a gimmick to rake in some extra dough. For starters, I couldn't begin to imagine by what type of mechanism a hot spot would be reduced. Does the IR light become polarized or change its properties in some other way as it's reflected off surfaces inside the lens? I mean, IR light is what we need to form the actual image, so, how can you separate one from the other when the two are the same and are mixed together?

Evidently, the price of such "coating" isn't cheap, so maybe there is something to it. So, my other question is: Does the AR coating itself introduce any adverse side effects? Again, I don't even have a starting point to begin processing something like that.

So, If the answer to my first question is Yes and to the second: No, then it makes a whole lotta sense to invest the extra $100 and here's a strong argument for it:

My D800 body isn't new by any means. I honestly, don't know how many clicks it's got left in it, so spending a lot of money upgrading it doesn't make much sense, especially it being just a "D800". But, let's suppose that I do pay the extra money for the coating, and it's working wonders and the camera just keeps clicking away. In that scenario I am actually, in a way, "future-proofing" myself by adding the AR coating. Let's suppose that my 24-70 G2 does not produce any hot spots at all, with or without a coated filter, who's to say that it'll be the only lens that I'll ever use for shooting IR? I will, most certainly, purchase new glass for my 'regular' photography in the future and I will, most likely, want to use some of those new lenses in my IR escapades as well. Now, those lenses may or may not turn out to be horrible, as far as IR hot spots go. In a scenario where I choose to install an uncoated IR filter I am the jerk who couldn't pay a little extra for a 'proper' IR conversion, now stuck with just his beat-up 24-70 for a lens and his worn-down Nikon D800 which isn't worth servicing anymore.

If it were only about the money, I'd shell out the extra shillings but, again, I need to know what the AR coating does to the image exactly, more importantly, the adverse effects.

The thing that would worry me far more is how do you know the G2 version of those Tamrons is any good for IR? and I'm not talking HotSpots.

Assuming you've been to Bjorn's site you'll see that he rates different nikon primes to their suitability to IR regarding IQ. Some lenses have no hotspot but also muddy, low contrast images. Who's to say the Tammy will work nicely? Most people seem to use primes, myself included.

the number of responses on the subject, which is zero,

I did. I convert Nikon DSLRs myself and use un-coated cut-to-size glass (fused silica actually) microscope slides as a replacement to the filter stack and have no issues with hotspots.

I need to know what the AR coating does to the image exactly, more importantly, the adverse effects.

It does nothing good or bad to the image per se. It allows more light to reach the sensor by preventing reflection from the surfaces of the IR filter. In reducing that reflection it should stop light bouncing back towards the rear element and around the mirror box that may be reflected back again as non-image forming light that can form hot shops.

As Petrochemist said further up..

"There are a VERY wide range of factors involved in hot spots."

I couldn't find (but that might be me!) any Plain versus AR coated filter comparison shots on either website. Curious.

If money isn't any issue, just spend it on the coated version.

If you EVER find a hotspot and you didn't spend the dosh, you'll blame yourself for being a cheapskate.

However, who's to say that same hotspot wouldn't have happened even with the AR coating??

Advertising will use weasel words like 'reduces' the frequency or severity of hotspots. They will certainly not say Prevents all Hotspots.

It is possible to remove hotspots from IR images in photoshop or some-such, but it is a bit tedious. DxO Photo Labs U-Point works well on RAW hotspots.

The thing that would worry me far more is how do you know the G2 version of those Tamrons is any good for IR? and I'm not talking HotSpots.

 

I did. I convert Nikon DSLRs myself and use un-coated cut-to-size glass (fused silica actually) microscope slides as a replacement to the filter stack and have no issues with hotspots.

 

I couldn't find (but that might be me!) any Plain versus AR coated filter comparison shots on either website. Curious.

 

If money isn't any issue, just spend it on the coated version.

 

If you EVER find a hotspot and you didn't spend the dosh, you'll blame yourself for being a cheapskate.

 

However, who's to say that same hotspot wouldn't have happened even with the AR coating??

 

Advertising will use weasel words like 'reduces' the frequency or severity of hotspots. They will certainly not say Prevents all Hotspots.

 

It is possible to remove hotspots from IR images in photoshop or some-such, but it is a bit tedious. DxO Photo Labs U-Point works well on RAW hotspots.

My point exactly, I get a non-AR filter and there are hot spots - I feel stupid. I send the camera in for a new, coated filter AND there are still hot spots - I'm a colossal moron who's also out of (additional) 500 bucks...

Thank you for explaining to me the bit where the light might bounce off of the filter and find itself bouncing back in as non image-forming light. I don't know why I haven't thought of it as I'm all too familiar with the same issue in non-IR photography. Old lenses, designed in the age of film did not take into account the reflectivity of a digital sensor. I've seen some horrendous ghosting and other weird stuff with old Nikkors and Sigmas, because of this very issue. With regards to coated IR filters, I don't think that that theory is sound simply because the very reflective sensor is still there. Yes, it's behind the "black" filter but it's infrared light so it can come back out no problem. Maybe the side that's towards the sensor is the one that's coated, or maybe both... I don't know, man. Daniel Malkin of LifePixel insists that the hot spots form inside the lens, so, there's no way to "filter them out", which is what I was saying.

On Lifepixel's site there is an extensive explanation and comparisons that form a strong argument against having AR coating on the in-camera IR filter. How convenient... But still.

So, I dunno, right now I'm leaning towards getting a non-coated filter installed because at this point, I think those hot spots will be there with or without it.

As per the lenses - you're right, I don't know that my Tammy will be good for IR. I'll just have to wait and see how this thing plays out for me. At this point I am not committing myself to IR photography. I'm merely converting an old camera body of mine for not that much money. If I see that it all turns out to be a total mess, with hot spots, muddy lenses and what not, I'll give it up altogether. I have so much on my plate as it is and I really don't need the extra hassle.

Daniel Malkin of LifePixel insists that the hot spots form inside the lens, so, there's no way to "filter them out", which is what I was saying

If a lens is a notorious hotspotter, you could indeed change it's (the spot, not the lens!) size by changing the aperture and i guess with one of the Nikon DSLRs with dynamic aperture control, you could watch it happen in LV as you stop down...:cool:

The size and intensity of the spot seems to be directly related to the aperture, if you get a big vague spot at f2, you'll get a much smaller but brighter spot at f16.

When I'm feeling really bored, I suppose I could set up my full spectrum (no filter stack) D600 in a dark room and illuminate a white wall with different colour LEDs. UV, BLUE, CYAN, GREEN, YELLOW, RED AND IR. I'll try and find my worse lens, and see what happens.

Why should I only get a hotspot in IR? Sure IR has material penetration properties, such as plastics and various organics, but eV wise it is the 'weakest' wavelength and the least refracted by a lens/prism... is that relevant to hot spot formation?

Were hotspots a problem with IR film? I don't think they were, but I wouldn't swear to it.... I can't remember!

If it wasn't, then with the same bodies (more or less) and same lenses, the only difference is film surface v sensor surface.

AFAIR Kodak HIE emulsion was a kinda satin pale grey on a transparent pinky polyester film-base with no anti-halation coating.

If a lens is a notorious hotspotter, you could indeed change it's (the spot, not the lens!) size by changing the aperture and i guess with one of the Nikon DSLRs with dynamic aperture control, you could watch it happen in LV as you stop down...:cool:

 

The size and intensity of the spot seems to be directly related to the aperture, if you get a big vague spot at f2, you'll get a much smaller but brighter spot at f16.

 

When I'm feeling really bored, I suppose I could set up my full spectrum (no filter stack) D600 in a dark room and illuminate a white wall with different colour LEDs. UV, BLUE, CYAN, GREEN, YELLOW, RED AND IR. I'll try and find my worse lens, and see what happens.

 

Why should I only get a hotspot in IR? Sure IR has material penetration properties, such as plastics and various organics, but eV wise it is the 'weakest' wavelength and the least refracted by a lens/prism... is that relevant to hot spot formation?

 

Were hotspots a problem with IR film? I don't think they were, but I wouldn't swear to it.... I can't remember!

 

If it wasn't, then with the same bodies (more or less) and same lenses, the only difference is film surface v sensor surface.

 

AFAIR Kodak HIE emulsion was a kinda satin pale grey on a transparent pinky polyester film-base with no anti-halation coating.

My old Nikkor 50/1.8D suffers from a "mild" hot spot in the visible light range. I first noticed it when I started using the lens with a digital camera. It was the same with the D70s, D80, D300s and the D800. Never used it with my new D850 and why would I? The lens is pretty sucky anyway. What happens is you begin to notice "something" in the center of the frame right around F/11. At F/16 it's much more obvious and at F/22 it's like "right there", a small but a very distinct bright spot. Never saw anything like it with either one of my F5's. So, what else can it be but the shiny sensor? No wonder that everywhere it says that this lens sucks big time for IR.

So, I'm feeling optimistic about by second-generation "Tammy" 24-70 and I think that I will place my order with Lifepixel for the 830 nm, uncoated filter conversion.

Just in case this is my last post in this thread: Thank you all for your time.

Seeing how lots of old threads keep popping up, in case anyone else wants to use the Tammy G2 for IR, maybe you'll come back and say whether it's a gem or a goat?

Sure, man. It's gonna take a while though. Getting the service done is one thing, going out into the desert to try and take 'actual photos' I can't tell right now when it's gonna be. But yeah, sure thing, if I still remember by then.

The D70 uses IR absorbing glass with a CCD sensor. Hot Mirrors are reflective in the IR, pass visible. CCD's are much more sensitive to IR than a modern CMOS sensor. The (very old) 1990s DSLR's used Hot Mirrors, the DCS420c and DCS200c are examples. The DCS200ir- no Hot Mirror over the CCD. The Nikon D1 uses IR absorbing glass.

Lens coatings are designed for the visible range, and many reduce transmission in the IR end of the spectrum. Near IR for a digital sensor is roughly 700nm to 1100nm, quite a range to handle for CA when most lenses are designed for the visible portion of the spectrum. Look for a lens that has the IR focus index very close to the main focus index. Use that as an indicator of relative CA. Macro lenses tend to be well corrected for CA. Zooms with lots of multi-coated surfaces- probably not ideal for IR.

That's the great thing about using UV LEDs, they emit zero IR! If you're working in a dark room you don't even need any filters at-all*!!

 

I am the proud (and now poor!) owner of a 2" Baader Venus filter....:cool:

 

* You do need a couple of UV trans filters on the 30W UV LEDs though, as they do emit some visible violet/blue up to about 425nm. Try putting..

"ZWB2 1.9mm Ultraviolet UV Band Pass Filter" into ebay search box. 42mm diameter for ~ $2. I stack 2 per LED.

I recently got a few ZWB2 filters but not tried them out yet.

I haven't tried shooting UV in a darkened room, that should help a lot if my UV torches are bright enough.

Apparently copper sulphate solution is quite effective at blocking NIR so I plan on making my own IR block filter at some point - I work in a lab so can get hold of the chemical easily :)

Apparently copper sulphate solution

That used to be the mechanism to 'get' cyan (490nm) light to do Cyan Induced IR Fluorescence, where the light source was a 2K arc light and the copper sulphate soln (in a big fish-tank) adsorbed the heat and all the unwanted wavelengths.

shooting UV in a darkened room

Don't forget the UV goggles! UV in the dark could well be permanently damaging... and 'cos it's dark, your pupils will be like saucers and allow buckets of 'bad' light in.... and trash your retina...:(

With 2 x ZWB2s stacked per LED you can't really tell when the lamp is on except by fluorescence of things in the vicinity. I often leave a piece of modern printer paper around as it's got a lot of blue whitener in it! Equally when shooting make sure there's nothing near by to ruin your shot by 'glowing'. Photographers wear black for a reason...;)

I prefer to use a proprietary Hot Mirror to block NIR, I picked up some pretty good Tiffen filters a while back in a bunch of sizes. Sometimes over the taking lens, sometimes over the light sources.

Others I know rely on info at Life Pixel and books by Deborah Sandidge and info on her website. .

Deborah Sandidge Photography

https://www.amazon.com/gp/product/047040521X/ref=dbs_a_def_rwt_hsch_vapi_taft_p1_i0