Frequently Asked Questions II
Selected questions and answers, based on the collective wit and wisdom of contributors to the original Black & White Photography Forum. Be sure to visit our Community and participate in current discussions. Our thanks to all who have contributed!
Spots on Negatives
Q. I have a Paterson Universal tank which can accomodate up to two reels loaded with 35mm film. I have not had any problems with this tank when I've used it to develop a single roll, but when I tried doing two I ended up with spots on some of the negatives. Have others experienced this problem? Does this have to do with the method of agitation? I have been using inversion. Is it better to use the little "spinner"?
A. If you're doing inversion agitation (the best way to agitate, IMHO), be sure to tap the tank a few times before putting it back down. That will release any air bubbles that might form when you've turned the tank over. (Mason Resnick)
A. I've had the same problem. I rap the tank on the counter after filling it, and after each agitation. I use the spinner to agitate rather than inversion. Generally this solves the problem. I also pre the film first (also rapping the tank) and then add developer with proper agitation and rapping. (Rick Athearn)
A. Another possible way of getting clean results is to use bottled water. It is nice and pure and clean. (Alan Orling)
Q. I have recently discovered the world of B/W Infared photography. Anybody out there with suggestions to what brand of film to use?
A. I've had great success with Kodak's IR film. I've used Ilford's but Kodak's seems to have abit more tonal range. I've used it in my medium format cameras and recently started shooting IR in a plastic Holga toy camera, pinhole cameras and some box Brownies that take #120 and #620 films with interesting results. I use a red filter and treat the film as if it were iso 100 but when taking long exposures the reciprocity factor is very strange compared to conventional emulsions. I process it in 2 parts water:1 part D76 which gives a fairly fine grain. Get a couple of rolls, shoot with it and have some fun. (Chuck Baker)
A. There are three choices to pick: Konica B&W 750nm Infrared, Kodak High Speed Infrared and Ilford SFX (SFX is not an infrared sensitive film; it simulates infrared sensitivity). Kodak is a very sensitive film to use. The infrared sensitivity is high. Do not load this film in the light. Konica's film is sesitive down to 750nm wavelengths. It is a lot easier to handle. Use both Konica and Kodak infrared with a deep red filter (#25). Your light meter will NOT be able to read infrared light, so you will be estimating. Hopefully you will get an info sheet with the film. Otherwise, guess at 1/30 @ f5.6 on a sunny day. (Dennis Oyama)
A. I've had some fairly good results with Kodak's IR film in 35mm. It is important to load and unload in complete darkness and a changing bag is needed in the field. I prefer the grainy infrared look and generally try to overexpose. I set the meter to ASA 200, take a reading and then bracket towards overexposure. According to Laurie White in her book "Infrared Photography Handbook", 1/125 at f11 is a good place to start. I have gotten good results by using this on a sunny day as well as by metering at ASA 200. If you are interested in a good introduction, I highly recommend Ms. White's book. (Henry Cheng)
A. Kodak HIE is the only "true" infrared commercially available. Konica 750 is close and can give IR effects. It is also the only 120 size IR film. Ilford SFX 200 and Agfa are extended red sensitive. Treat HIE as 200 to 600 metering through the lens with a #25 red filter and 125 with a hand held meter. Do not figure any further filter factor. I treat Konica as ISO 12 using a hand held meter and a #25 filter. (James Wood)
A. I use Kodak High Speed infrared film in a Leica M3 rangefinder camera with a #29 deep red filter and lens cap. I keep the lens capped until I actually make the exposure. The Leica allows me to view the scene sharply when the lens is focussed for IR because only the RF patch changes. When I use the reloadable Leica cassettes, I find I can load the camera under low light with no fogging since they use an opening slit instead of felt. My usual exposure in summer, under bright sun (North America) is 1/250 at f 11. I find my negatives are a lot less grainy than most I see published. They are developed in FG-7 1:15 for about 9 min. at 68 degrees F. Be careful of using OM series cameras for IR. I got patterns on the film from the pressure plate dimples. So it seems a lot easier to use a RF. (Alan Magayne-Roshak)
Q. I am just getting into B&W and hope to build a darkroom soon. Until then, I'll be using a commercial lab to process and print. With that in mind, what type of black and white film would your recommend? I recently shot Tri-X, but the results were dissaspointing.
A. I've had good results with both Tri-X and XP-2. When XP-2 is commercially processed it often comes back with a brownish, sepia-like cast which many people find pleasing. Some labs can print it up for you on B&W paper if you dislike the color cast. Before I set up my bathroom darkroom, I frequently got disappointing results with B&W film in general. I believe that this is because many places, especially "cheap-o" labs do very little B&W business and are not geared for it. I did manage to get decent results at a lab which catered to professionals but that was significantly more expensive. In my opinion, Tri-X is an excellent film for the beginner. It is fairly affordable and forgiving. Don't let your single negative experience (pun intended) deter you from using it in the future. (Henry Cheng)
A. Sticking to the XP2 until you can do your own processing makes sense. When you get your own processing setup, Tri-X is excellent and I like T-MAX 400 (Kodak) even better. However, it has a very low (maybe zero) tolerance for overdevelopment. I teach photography at a small college and we've been using HC110B developer for 6.5 mins. at 68 degrees F. We use diffusion enlargers. Results are excellent. (Charles Ellis)
A. XP2 is a delightful film with a fine grain, smooth tonality and wide exposure latitude. For a 'newbie', it is indeed a nice film. XP2 does have a rather long 'toe' and a bit of a shoulder; this means shadows and highlights will have reduced contrast, making the negs a little easier to print for some. I've found that Kodak T400CN offers the advantages of XP2 (exposure latitude and consistent C-41 processing) with TMax qualities (finer grain, sparkling mid-tones and the ability to print truly brilliant highlights with detail). T400CN is quickly replacing TMY as my EI 400 film of choice. (Dana Myers)
Best Web Scans
Q. What kind of post-scan tweaks must be done to hold down file sizes of my scanned B&W images that are destined for the web?
A. Start by saving your scans as a TIFF while you work on them in Photoshop. After you get the image the way you want it and want to put it on your web page, make a copy of it, save it as a JPEG, reduce the image size to about 2 "X 3" (approximately--just DON'T send an 8X10 sized image, it'll take too long to download) horizontal or vertical, reduce the gray levels as much as possible without deteriorating the tonal values, and copy to your page. This should get your file size down. (Gerald Boles)
A. I've used a number of scanners and to tell you the truth on the web it really makes no difference. Eveything on the web should be reduced down to 72dpi or less. I personally try to get the full JPG's down to 30k. I save all my images as TIFF's (better quality) then use Photoshop to reduce them down to 6x4 @ 72dpi. This provides a good viewing size, while keeping it at a resonable byte size.
GIF Vs. JPEG?
Q. Is GIF better than JPEG? Also are 5x7's better to scan than 8x10's? Any input would help.
A. I found that my jpeg files (all RGB at 72dpi for B&W in Photoshop) were about 1/3 to 1/2 the size of the gif files (all indexed color at 72dpi, again in Photoshop) of the same image at the same image size (in inches). The gifs were about 30K, and the jpegs were as small as 8-10K for the same image. My problem was the look of the JPEG files, which completely fell apart. Whatever subtle gradations a 72 dpi images can hold on the monitor were gone with the JPEGs. I went back to the gifs. They hold together much better, though they do take a little longer to load. Still, no comparison to a well made B&W print. (Jim Schoppman)
A. The biger the file the better the quality. I can cut the size of a gif in half and lose very little quality by transfering from gif to jpg at 39% quality factor on Corel Photo. (Dennis Seyer)
A. JPEG is definitely the way to go for photographs. GIF files are by their nature limited to 256 colors (or 256 grey tones in the case of greyscale images) to compress the image. JPEG JPEG (which stands for Joint Photographic Experts Group) was expressly developed for continuous-tone images such as photographs that would suffer if reduced to 256 tones/colors.
JPEG works on "sequential encoding" where each image is encoded in a "single pass" from left to right and top to bottom. The new Progressive JPEG standard encodes the image in multiple scans, with a coarse scan first, then succesively improved scans. JPEG allows you to set the level of compression, which directly affects the quality of the image. If you got poor-looking JPEGs, you must have compressed the hell out of them. A JPEG at the lowest compression setting is virtually indistinguishable from its Photoshop original. If you surf by my gallery at http://www.interlog.com/~chrome you can see images where I've used High Quality compression, which is the second least compression level. (Martin Mraz)
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