philip_baltar

<p>What I was getting at is that using a profile <em>only</em> for soft proofing is useless without additional information. You also have to know which rendering intent will be used for printing. Based on what I've read (and experiments with my home printer), different rendering intents can make a big difference in the amount of detail you get in saturated areas (certain strong colors) and shadows.</p>

<p>Since I'm likely to be using Adorama and I'm sure others here have used them too, maybe I should ask a more specific question. Can I get Adorama to not do <em>any</em> correction whatsoever? I'm capable of applying their ICC profiles on my own, so I don't want them to apply the profiles a second time. Their FAQ page about this is unclear.</p>

<p>Disclaimer: I'm an engineer, so I'm hesitant to use any process that I don't fully understand.</p>

<p>The issue is that a color space conversion WILL take place at some point between us sending the file to the lab and the operator pulling a print out of the printer. This will happen either in software because the operator intentionally converts it (or the printer is smart enough to know its limitations), or in hardware because the printer simply isn't capable of printing certain colors due to ink limitations.</p>

<p>Now, if the color space conversion happens intelligently (not just the printer trying to do something it can't), then we have the issue of different conversion methods producing different results. We'll get a different result with the relative colorimetric intent than with perceptual (or with absolute colorimetric or saturation). So, when we soft proof, we need to know which intent is going to be used when printing. Without knowing that, you only have a 1 in 4 chance of having the print match the soft proof on your screen.</p>

<p>If you don't believe me, try it yourself on your home printer (as I just did). Soft proof an image and watch how the different rendering intents change the image. Then print the same image using the different rendering intents. If you get the same results as I did, you should find that the print only matches the soft proof on your screen when both use the same intent.</p>

<p>I profiled my printer myself and I seem to be getting good results. If I simply print something, I don't get what I see in the soft proof. However, if I convert it to the printer profile, then print, I get what the soft proof says I should get. Of course, the printer driver doesn't use ICC profiles, so I guess it makes sense that I have to do it manually. Though, I'm still a little fuzzy on exactly how all of this works.</p>

<p>If the lab provides me with an ICC profile, I know what their printer is capable of doing. However, they're expecting a file in sRGB (and from what I've read, some printers have serious problems if you embed a different profile). So, what do I have to do to get a print that looks like the soft proof? Do I send them the raw sRGB file? Do convert to <em>their</em> profile, then convert back to sRGB to take care of out of gamut colors? I could also convert to their profile, but not embed it so that they assume it's sRGB.</p>

<p>----------------------------------------------<br>

In case anyone is curious:<br>

Linux has everything you need to have a fully color managed workflow. The only proprietary software I had to use was the factory program for my scanner (I couldn't figure out how to tell the native linux programs to no do any color correction). I even found an open source colorimeter (that's right, open source hardware). I profiled my monitor with the colorimeter. Then, I got an IT8 target to profile my scanner. I then used my profiled scanner to profile my printer. I got satisfactory results, but I'm not a pro, so I may have no idea what I'm talking about.</p>

<p>After you install argyll, they have a nice tutorial here: <a href="http://www.argyllcms.com/doc/Scenarios.html">http://www.argyllcms.com/doc/Scenarios.html</a><br>

Wolf Faust in Germany makes some cheap (but supposedly high quality) IT8 targets: <a href="http://www.targets.coloraid.de/">http://www.targets.coloraid.de/</a><br>

For your open source colorimeter needs, you can turn to ColorHug: <a href="http://www.hughski.com/">http://www.hughski.com/</a></p>

 

<p>I'm getting back into photography after a number of years. Now that I have a fully digital workflow, I decided that color management would be a good thing. So I went ahead and profiled all of my computer equipment. Though I have a mid-range photo printer sitting next to me, there's various reasons I would want to send things out to be printed (most notably would be larger prints).</p>

<p>I'm trying to figure how to properly use the ICC profiles from the labs. Most of the stuff I've read says to convert the image to the appropriate profile. I've found that I need to do that to make my own printer print correctly. However, the comments in Adorama's FAQ imply that the profile should <em>only</em> be used for soft proofing:<br>

<a href="http://forums.adoramapix.com/entries/228224-color-calibration-and-custom-correction">http://forums.adoramapix.com/entries/228224-color-calibration-and-custom-correction</a><br>

So, should I or should I not <em>convert</em> the image before sending it out to be printed? I'm using linux, so if anyone has instructions specific to GIMP, that'd be great.</p>

I've been doing research on making black and white slides. From what

I understand, you develop then bleach (instead of fix). This would

make a positive instead of a negative because it removes the exposed

silver halides (now metalic silver after being developed). From this

point, the film is re-exposed and developed again, then fixed. This

converts the remaining halides to metalic silver, "stabalizing" the image.

 

This would mean that the only from between normal black and white

negatives is the bleach. Some guides I've read, however, use

different first and second developers. If I understand the theory

correctly, the second developer's job is the convert ALL remaining

halides to silver (any unwanted stuff would have been taken care of

the first time around). Is it important to use two different ones? I

use HC-110 and Kodak rapid fixer for negatives. Would this get the

job done?

 

Also, could I use E-6 bleach for this? I'd rather not have to gather

the raw chemicals and mix it myself.

I'll probably get yelled at for saying this, but I always use JPEG. The exact number of saves you get will depend on your software and all your settings. For me, I've found that as long as I use lower compression, there's not much loss. My scans are high resolution, so much of the degredation gets lost (hidden, rather) when the image is shrunken (or otherwise rescaled). Personally, if I inspect the images closely at 100%, I see a minor loss in sharpness, but you can sharpen it anyway. I'm also sure that you'll need to take a magnifying glass to my 8x10s to see any serious problems.

 

The reason I use JPEG is that the files tend to get too big. A file in an uncompressed/lossless format is in the 20mb range. Depending on what I'm doing, I'll have three or four interim files before the final one. That means I'll have around 80mb of files for each image I work on. If I stick to JPEG, each file is only in the 3mb range.

 

If I was working on something important, I'd probably stick to lossless formats though. For me, photography is a hobby not a business, so I can get away with some minor losses in quality if it means it makes the rest of my life easier.

Hey! Coincidentally, I just got a chance to do the same at the San Jose Grand Prix a couple weeks ago. I've never done it before either. I was using a 70-300mm (mostly in the 200-300mm range) on my Rebel 2000 with Sensia 100. I ended up with exposure problems though. I'm not exactly sure what happened, but I'm thinking that the combination of shiny cars and dark pavement may have messed with the metering. It could have also been my panning. The camera may have metered in a spot different from where the exposure was actually taken. Of course, I was also using a polarizer, which seems to also mess with the metering...but that's for another thread. I was using aperture priority at f/8. That was giving me shutter speeds of 1/250 - 1/500. I didn't get much of a blurring effect even with 1/100, probably because I was up in the stands and too far from the track.

 

If you'd like to see what I got, you can take a look at my stuff here: http://ratlab.dyndns.org/temp/grandprix/1/index.html

 

It'll only be there for a week or so, so take a look at it before it goes away.

I've had much better results with straight tap water than with water and photo flo. Of course, we've got a water softener here...

Well, after several attempts, I finally found this in the bowels of google:

 

http://www.pmb.net/projects/canon_lens.html

 

So, I decided to open up my lens and found the problem. With that, does anyone know where I can buy gears?

Does anyone know of any autofocus slr lens repair guides? The

autofocus on one of my lenses seems to be broken. If it's in a

certain range, it'll move a little then stop. Otherwise, it makes two

quick buzzing noises and doesn't move. Manual focus works fine

though. I suspect that there's a broken or misaligned gear somewhere.

 

The lens is only $120, and I have a feeling that pro repairs would be

at least half that. I'm looking for a guide so that I can see whether

or not I should attempt repairing it myself. If it's too complicated,

I'll just live with the problem.

Anything like this?

<P>

<A HREF="http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=00AGvJ">http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=00AGvJ</A>

More FYI...the cap is part# CB1-340B-000

Well, I bought 3 from Canon. FYI, the number for the parts department is 1-732-521-7230 (M-F, 9 a.m to 8 p.m. ET). 80 something cents each. Here's the catch: $5 shipping. It's probably UPS or something. I can't believe that they don't just stick it in an envelope and mail them to me for 32 cents.

I lost the little plug that goes in the remote port for my Rebel 2K.

Does anyone know where I can get a new one and how much it costs? I

suspect that if anyone sells it, I'll be way over priced. I know the

general area that it's in, but it's in the grass. I just need to know

whether I should go look for it or just buy a new one.

Would there be any problems leaving film in water for about an hour

after it's been developed and fixed? I develop in the same bath tub

that I hang it in and my tank only holds 2 reels. If I want to do

more than two I have to hang up the film while I develop the others.

I've had some dust issues because of this.

I've been using this:

http://www.photoscientia.co.uk/Gamma.htm

 

I don't have a reference, so I have no idea how accurate it is.

 

Maybe someone set to gamma 2.2 from a spyder can let me know?

Just a tip:

I'm sure you've gotten the email saying that some guy got his face burned by heating water in the microwave. Supposedly, you can super-heat water past the boiling point, then when something is introduced into it - like a stiring impliment - it'll explode. The Discovery Channel's MythBusters found that this CAN happen if you use distilled water. 125F is well below the 212F boiling point of water, but I just wanted to let you know.

 

Anyway, I don't bother taking the temperature. I just use whatever feels warm out of the tap and I haven't had any problems.

Hm...I was just looking into this a few days ago. After a few hours of research, here's what I found:

<P>

Scala uses some odd process, I was only able to find a few labs that do it, not sure if you could do it at home. If you're looking for black and white slides, you can use Tmax 100 and a slide developing process (not E-6). Kodak makes a kit - Tmax Direct Positive Developing Outfit. People claim that it's about $30, but I haven't been able to find anyone that sells it AND will ship it to me. B&H has it - $36.50, but they won't ship it.

<A HREF="http://www.bhphotovideo.com/bnh/controller/home?O=productlist&A=details&Q=&sku=29115&is=REG">Link to B&H</A>

<P>

I found a homebrew version though - it's the last article on the page:<BR>

<A HREF="http://www.rit.edu/~andpph/pf-faq/faq-16.html">http://www.rit.edu/~andpph/pf-faq/faq-16.html</A>

<BR>I still haven't figured out where to get the chemicals though.

I don't have either one (though I wish I did), so don't consider me an expert on it. If I were presented with that problem, I would check the batteries. It's been my experience that most intermittent problems with electronics are caused by the power supply. Either the battery is dying or the contacts are dirty. You could also check the contacts on the card/card slot. Not sure how to though...

I haven't tried it, but I think that memory card cases are about the size of a slide.

Ok, well, I checked on the slides using a different setup. This time I used a lamp with a flourecent bulb and put the slide on my flash diffuser. I put the diffuser as close to the bulb as possible without actually touching it. All of them - on both rolls, including those without the polarizer - have the magenta cast. It seems that if the exposure is off - underexposed - the cast is stronger. I've got one with darker and lighter areas so that you can see it. The scanner seems to be reproducing it very well though.

 

So do you think it was the film or the processing? My lab is usually good with my negatives, but lately I've been having some probems...<div></div>

<<You mentioned a roll that was stored in the freezer... was it fresh film?>>

 

I don't remember the exact date, but it was the latter part of 2005. I took it out the night before and left it at room temperature. Anyway, the first roll - the first pictures I posted - weren't frozen. Only the second roll was. I froze it because I didn't know when I was going to get around to using it. The only reason I went to the observatory was for a class. I decided to take advantage of the trip and take some pictures.

 

<<Did you use the polarizer at "max" effect? I've noticed thay do strange things to color when used at max position (rotation)>>

 

Yes, I did. I have some without the polarizer, but they weren't with the same lens. It was hard to tell if the cast was there though. I'll get around to scanning them when I get home.

 

<<Anyway, haze is a bitch, so maybe you could time your shots after a rain so the air is clear (but no fog).>>

 

I thought of that, but the drive is about an hour and a half. I probably won't be back there for awhile. I went a few days after some showers though.

Well, I looked at them using a flourecent light and whatever light an overhead projector uses. A few of them do indeed have a strong cast, but others are harder to tell - I'm assuming that there still is though.

I suspect that the "grain" is a combination of things. First off, it could be noise from having such a long exposure. It could also be artifacts from the photoshop processing. My guess, though, is that the biggest contributer is that you're picking up pixels from the screen. Personally, I would have used a light or the sun.

 

I was considering doing something similar, but I decided that wouldn't get the results that I wanted without a film scanner. Anyway, I'm in electrical engineering, I don't do mechanics.

This one has the polarizer on the left half only. I was just playing with it, so the exposure isn't that great.