rodeo_joe1

Thanks for those links John. I also found various other snippets of information on the Web. There was one containing a maker's claim of 1150 flashes per charge (!) - sounds unfeasible, right? But when the Lencarta rep was asked outright if that was full-power flashes, he evaded answering. No surprise there, then. Anyhow. I left the unit fully charged and unused for over a week, and then found I could squeeze 120 full-power pops, at 10 second intervals, out of the battery. That'll do. It's about what I expected. The Chinese origin of the kit is given away by the amusing directions printed on the battery - "Do not dabble." and "Fever in using, charge battery after cooling." A reminder to pack some cold beers or Malaria tablets when on location perhaps? I might still look into converting the battery pack to 4000mAh Lithium-ion cells... but the price of those has rocketed recently. Ah, for 55 quid plus auction fees I think I did OK though.

To answer one of my own questions: It seems that I struck lucky with the battery condition. I got over 100 full power pops from the battery with both heads connected. I can live with that. I could find absolutely no trace of an instruction manual online. Lencarta seem to have erased every trace of this item from their website, and it appears no-one else has archived any hard info about it online either. Doing a bit of maths - dividing the 3000 mAH/24 volt battery capacity by the stated 600 watt-second flash energy - shows that 120 pops is a reasonable expectation. As a comparison, a modern 75 watt-second speedlight running on 2500 mAH/5.2volt NiMH cells gives maybe 170 full power shots, which is about the same ratio between battery capacity and flash energy. The recycle time of the Lencarta "Safari" isn't exactly speedy though. Recycle time is at best 4 seconds, and this lengthened to over 5 seconds as the battery wound down. I'll just have to wait and see how the battery holds its charge during storage without use. However, the battery casing is huge and would easily take 24 volts worth of 4000 mAH Lithium Ion cells, with plenty of room to spare for a battery management circuit. The Safari battery pack next to a speedlight for comparison. The battery pack also weighs at least twice as much as the speedlight!

The nominal voltage of a single Li-ion cell is 3.7 volts on load. 4.2 volts is given as the maximum charging voltage and would only be seen for a short time as a terminal voltage on a freshly and maximally charged cell off load. Two series connected Li-ion cells with a nominal terminal voltage of 7.4 volts should be fine to feed into an SB-800. However, you could drop the voltage by putting a 10 amp rated silicon rectifier diode in series with the cells - just to be utterly safe. The diode will drop about 1 volt at the ~ 8 amp draw of the speedlight during initial charging. Giving a voltage at the speedlight of between 6.4 and 7.8 volts, with the latter being an absolute maximum with freshly-charged Li-ion cells at no load.

To slightly redeem my experience with the shoddy Vario-Tessar: I've since acquired a Sony-Zeiss 55mm f/1.8 ZA Sonnar and a Zeiss 25mm f/2 Batis, used and in VG condition. They're both optically excellent and aquit themselves extremely well on the 60 Mpx a7riv, even in the extreme corners of the frame and wide open. Auto focus is fast, accurate and near-silent. However, I did reject one sample of used 55mm ZA Sonnar I was offered, due to centre-frame smearing that was obvious even in a magnified viewfinder image. Damaged by a former owner? Who knows. All I can say is; if you get a good 'un, the 25mm Batis or 55mm Sonnar are very, very good. But then that could apply to quite a few lenses.

Sounds like a good way to grow a baking soda wart on your finger! 😀 There's epoxy putty as well, which I can vouch for as easier to work with, and it sets iron hard. I've successfully repaired things from tripod bush knobs to a vacuum cleaner with it.

My used 17-55/2.8 Nikkor had some noticeable de-centring, as well as being ridiculously large and heavy for a DX lens. I bought a much lighter and neater Tamron SP 17-50/2.8 new for about the used price of the hefty Zoom Nikkor and got equal or better IQ. Anyone want to buy a 17-55 DX Nikkor that's seen almost no use whilst in my ownership?

A bit late here, but I'll add that a dropped lens, with camera body attached, probably won't escape without some optical or focussing damage too. So although it might look like "just" the mount has been wrecked, until it can be mounted to a camera and re-used; who knows what else might have been damaged too? IME a lens with obvious signs of physical damage, even something like a dented filter ring, might well perform below par optically as well. I'll definitely second the BER (beyond economic repair) diagnosis. Because repair would be a can of worms not worth opening on a cheap lens like this.

Just an observation: I don't think repeated regular shallow discharge and recharge cycles serves the batteries well. So, how far discharged do your batteries usually get in a day Bill? If it's only to 50% or above, then it's probably better to continue using them until they really need recharging. Apparently Lithium-Ion cells are supposed to stand over 500 charge/discharge cycles; that's according to some published specs. Which would be nearly 18 months of daily deep discharge use. I usually use my camera batteries until they're at 10% or less before changing them and putting them in the "to be recharged" space in my gadget bag. That way I've had several years use out of genuine Nikon batteries. However, that's using 3 or 4 batteries in rotation. What!? You have to remove the battery door to change batteries on a Z9? That's just crazy.

I just bought an old Lencarta branded "Safari 600" flash kit at auction - a real auction not Ebay! It comprises two heads and a 600 watt-second battery-operated power pack. It all seems to work OK, but I have no idea how old or what use/abuse this kit has had. My concern is with the 24 volt NiMH battery pack. Spares are apparently Unobtainium and would no doubt be ridiculously expensive. So my questions are, if anyone has experience with this kit; what number of full-power pops is reasonable from a fully charged battery? And how frequently does the battery need charging in storage without use? I obviously don't want to lug it on location only to find it go flat on me after a few pops. Although I can't complain too much if the battery capacity is reduced, say, to half what it should be, since it only cost me about 1/10th of the new price. Info on the kit for the curious: The power pack supplies one or both heads simultaneously, dividing it's maximum 600 ws equally between heads. The heads cannot be controlled individually. Triggering - at a safe 7 volts - is by 3.5mm jack from the power pack, and "Power" is continuously variable on the power pack down to 1/8th power. Tests so far look promising. One head with standard 6" (Bowens-S fit) reflector gives a measured 100 ISO GN of 40(m) ~ 130(ft) and the CT remains fairly constant with varying power. In a softbox brolly the same head allows an exposure of between f/9 and f/10 at 2.5 metres. Also, the flash exposure will easily overpower overcast daylight, and pretty much balances full sunlight. So far, so good. I expect only time will tell how limiting the lack of control over individual head output will prove to be. Although I'm fully prepared to augment the two head kit with a speedlight or two. Grateful for any additional info on this Lencarta or Jinbei outfit.

Old film-shooting adage: "Expose for the shadows and let the highlights take care of themselves." WRT spot metering - this assumes 1) you have a spotmeter, 2) the spotmeter has a narrow enough angle and is baffled well enough to cope accurately with shadows adjacent to bright highlights - not many are - 3) you know what you want as a mid-tone, and 4) the film can cope with both highlights and shadows. If it can, then there's little point in spot metering at all and an average reflective or incident metering is all that's needed. Another consideration is the 'flare factor' of lens and camera. With the setup shown, which has a large area of highlight compared to shadow, the shadows will automatically get 'filled' simply from camera body flare and internal lens reflections bouncing light about. Especially if it's an old single or non-coated lens.

'Spool creep' is a well-known issue with rollfilm; where the film has a sloppy winding with sufficient gap between layers to allow a streak of fogging. It's more common at the end of a roll when unloading though. So are you sure it's the first frames that are fogged and not the last? When I shot MF I used to keep a 6" wide strip of kitchen foil in the gadget bag; to quickly wrap unloaded rolls in and keep them light-tight.

Update on the above. For years I've owned a Zeiss 50mm f/1.8 Planar in Rollei QBM mount, but had no working camera to use it on. However I recently bought a QBM adapter for the Sony A7r4 and so have been able to put the Zeiss Planar through its paces. I'm impressed... very impressed. Corner sharpness is very good wide-open, and comparable to the Zeiss/Sony 55mm f/1.8 Sonnar. In fact the LoCa fringing of the old Planar is far less than that of the far more expensive Sonnar, but it does show a slight amount of spherical aberration wide open. This disappears at f/2.8 and the two are pretty much equal from there on. BTW, the Rollei/Zeiss Planar is nothing like the original double-Gauss 6 element Planar. It's an asymmetric 7 element design with a Gauss-type rear section and 4 separated elements in front of the iris. I'd certainly recommend the Sony/Zeiss ZA 55mm Sonnar for astro work with a Sony MILC, but if you don't have that sort of money to spend, then the Rollei Planar can be got used for well under half the price of the Sonnar.

To put 230 Joules into perspective; it's only the same energy as 3 decent speedlights, be they Chinese YN560s or Japanese Nikon SB25, 28, 800, 900, etc. or their Canon equivalent. But capacitor energy is not exactly light output. Because the tubes are smaller, with a lower retaining voltage, and their reflectors are far more efficient, speedlights put out a fair bit more light than a studio 'strobe' of the same energy rating. So a 200 watt-second strobe in a softbox is roughly equivalent to the same size softbox containing two speedlights on a twin mount. And without the trailing cables if you use wireless + optical triggering.

Yes they do. Light is reflected diffusely from the image plane - be that film or digital sensor. That light is not totally absorbed. It bounces around the 'dark chamber' and makes its way back onto the sensor, thereby contaminating shadow areas with extra light and limiting the 'dynamic range'. This has nothing to do with noise. In fact, as I previously said, the extra light performs an optical compression of the subject brightness range and helps the sensor cope with extreme subject contrast.

Just curious. Have Nikon stuck with the same 39mm filter they used as a 'drop-in' on the old Reflex Nikkors and large-aperture teles from the F-mount days? TBH, I could never detect any difference in IQ with the 39mm UV filter fitted or not, apart from a slight shift in focus, but since all the lenses taking a rear filter focussed past infinity, that was no issue.

Too true. I haven't checked PN for about 6 months, and in that time I can count the number of new threads without taking my shoes and socks off. It also beats me how a film-camera query posted before the site re-vamp gets resurrected into a purportedly "mirrorless digital cameras" forum

The modelling lights are what get the units hot. If you don't have the modelling lights on, then there's no reason for the fans to kick in. A flash tube does put out a huge "heat-wave", but it's over in a few milliseconds and doesn't have time to heat up the flash head significantly.

975V to get a pitiful 230 Joules! So that's why, if we're sensible, we don't use old studio flash equipment from the Jurassic era. Or from before the big bang - literally.

As has been said, the "scratches" aren't parallel to the frame edge, and are also not sharply defined. Ergo they aren't scratches, but minor streaking, most likely from processing. However, in the lab's defence, a very thin negative will show the slightest variation in density, due to the amount of contrast-boost needed in scanning. And, hey, it's film! If you want better image quality and total consistency shoot digital.

Hmm. When a 2TB 3500 MB/s NVME strip only costs around £100, then those CFxpress cards (probably using the same basic chipset) don't look very competitively priced.

But guys; who has such a throughput of film these days that simply writing on the negative sleeve or storage album page isn't sufficient enough record-keeping? Surely if you need to know time, date, shutter speed, aperture, GPS location, wind direction and relative-humidity at the time of shooting, then film ain't the medium to be using.

Sorry for delayed reply. Not checking this site regularly these days. Contact cleaner has a lubricant ingredient, whereas IPA has a dessicant action. The IPA will clean any contaminant off the track, but will increase the surface friction, which may impact the working life (if there's any left) of the resistor track. In short, I wouldn't choose IPA in preference to a proprietry contact cleaner. It'll clean, sure enough, but long-term.... who knows?

But most landscape pictures aren't just one small highlight surrounded by total blackness. The 'contamination' of light into shadows consists of the partial and diffuse reflection of all the light hitting the sensor, bouncing off the walls of the 'dark' chamber. Not even considering lens flare. Metering theory would have us believe that an average scene reflects about 13% of any highlight brightness. So if we take our sensor + dark chamber as reflecting 0.2% (20% x 1%) of the total image-forming light back into the deepest shadow, that's a minimum shadow brightness of 0.026% (13% x 0.2%) of the highlight brightness, given an 'average' scene. Which translates to a brightness ratio of just under 4,000:1. Or just over 2 full stops short of a 14 stop 'dynamic range'. So my contention is that a 14 stop DR is just not practically possible until the dark chamber of a camera - including the rear and internals of the lens - is made capable of reflecting absolutely zero of the image-forming light. BTW. Multiple images at different exposures will still have the same limit to their individual brightness ranges. And the light reflected back into shadow areas actually helps in revealing shadow detail, in the same way as the old trick of pre-flashing film did.

The 'dynamic range' - AKA brightness ratio - that can be captured in real life has almost nothing to do with the sensor or electronics of a digital camera, but rather its mechanical construction. It's all about internal reflection of light from the dark chamber of the camera, including the rear of the lens and any additional 'extension tube' that the lens might incorporate. Capturing a 14 stop 'DR' requires a brightness ratio of just over 16,000:1 to actually hit the sensor. And in turn that depends on no more than 0.00625% of the highlight brightness reflecting back into the shadow areas of the picture. Now the best matte black paints or flocking materials in common use have a reflectivity of about 1%, integrated over a 180 degree solid angle. Worse than that at small angles of incidence. While the reflectivity of a digital sensor is probably in the region of 20%. So, in order to get only 0.00625% (or less) of the highlights of a scene illuminating the shadow areas, you're effectively asking two surfaces with an aggregate reflectivity of around 0.2% to magically attenuate the highlights by a further factor of 30!? That's a big ask. OK; that's a worst case scenario where the shadow area is a tiny percentage of an otherwise bright scene. Which begs the question - "What is an 'average' ratio of highlight to deepest shadow area?" 10%? 20%? Even if it's only 5% that still leaves about 50% of the reflected light bouncing around between camera body, lens and sensor to somehow get entirely lost. In conclusion; achieving a 'dynamic range' of more than 14 stops looks like pretty much a wild pipe-dream for the majority of real world scenes. Unless you want to stick to subjects that are nearly all pitch black with only a tiny proportion of highlight area. Maybe the moon on a good dark night and shot with a 24mm lens?

My test chart just squeezes onto a sheet of A4 hi-res printing paper at (36x8) = 288 mm wide by 192 mm high. Unfortunately my inkjet struggles to print more than a 3 lines/mm element clearly, so it can't test the lens resolution to anything like its limit at an 8x reduction. But even 24 lppmm at the image plane is enough to give a good impression of how sharp the lens is, and things like CA, poor contrast and astigmatism show up quite plainly. FWIW, I've used the Sony's pixel shift on the same chart at a 1:50 RR, giving a maximum 150 lppmm image-plane resolution, and it turns out that most 'bog standard' 50mm standard lenses can easily resolve that at f/5.6 to f/8, even in the extreme corners. The visual IQ is much more affected by contrast, coma, distortion, CA and general 'smearing' effects than by pure resolution though. WRT coatings. A lot of my enlarging lenses have the old single, blue or amber coatings, but the El-Nikkor N has Nikon's green tinted multi-coating. So it should be fairly flare resistant.