Slide Films for 2X (or greater) Marco Photography?greenspun.com : LUSENET : Large format photography : One Thread
I am wondering what type of silde films do you guys use for the Macro Photography which requires 2x or great macro abitliy.
I was trying to take a picture of my watch with Arca-Swiss F-line Monorail and a 120mm/F5.6 lens. I extented the bellow for 410mm and the bellow extentsion factor is 11.6 (410^2/120^2) (!!!). My spot meter read 15s/F64 (ISO 100) and it means I need to get 384mins exposure time without adding the "film-getting-tired-factor" (what is the term?)
Now, I know that there is no film able to exposure for more than 30mins, and I am wondering what is the film of your choice for this situation. Any suggestions are appreciated and welcomed.Thanks.
-- Danny (email@example.com), January 24, 1999
The term you're looking for is reciprocity failure. Genrally the slower tungsten balanced films, Ektachrome 64T and the Fuji equivalent are well corrected for reciprocity failure.
I'm a little baffled at the calculated length of your exposure. What part of the watch did you meter? Wouldn't an incident reading be more useful under the circumstances? Calumet sells a very handy bellows extension calculator - a 1" plastic square target and a ruler to measure the image of the target on the GG with the exposure compensation written in for each magnification ratio. I have had very consistent results with it.
Granted, I haven't done a heckuva lotta macro work. The most extreme situation I can remember was when I used a 150mm enlarger lens to get a 2x of a sea shell on 4X5. The B&W film I used was expired Kodak Contrast Process Pan ISO 50 or so for tungsten. My exposures ran 15 minutes (at the longest) at f/45 with a 300 watt reflector bulb and a fill card. The bulb was maybe 3 - 4 feet from the shells.
I can only suggest more wattage. I will be very inteerested to read the answers of the more experienced macro shooters out there.
Calumet makes a very handy plastic bellows compensation device, a plastic 1 inch square target and a ruler to measure the image of the target on the GG. I have used that almost exclusively with very goo results.
-- Sean yates (firstname.lastname@example.org), January 24, 1999.
Thanks for the quick response, tips and suggestions.
Actually, I put the 18% grey card on the top of the subject (watch) for metering. I also use an incident meter to verify the parameters. Both incident and spot meter gave me the similar values.
Thanks for the tip on the bellows extension calculator. Instead of punching my calculator and use a 50mm rulers, I think it will be a much better way to take photograph. I think I had calumet 94 catalog somewhere.(Boy! I did not use my 4x5 camera for a long time and I am using Nikon coolpix 900 instead.) I will try to find it out and get some neat stuff from them. Thanks.
-- Danny (email@example.com), January 25, 1999.
The exposure factor in this situation is indeed 11.6. Now, 11.6 times 15 is 174 seconds, or about 3 minutes. Reciprocity failure means you need, I don't know, say 5 minutes. Where did you get 384 minutes from?
-- Alan Gibson (Alan.Gibson@technologist.com), January 25, 1999.
Your calculations are way off...A. Gibson's answer is closer. BUT a much better solution for calculating bellows extension is to use the Calumet chip or another equivalent to see the exposure factor directly without the calculations. The reprocity problem...well one answer is more light. Another solution is to use a telephoto type lens whch dosen't require nearly as much bellows extension..OR rent an APO - macro type lens (Nikkor or Schneider)which will allow you to basically do the same thing
-- C MATTER (firstname.lastname@example.org), January 25, 1999.
Thanks Alan Gibson and C Matter for the reply. Yes, indeed, I realized that my calculation was wrong. (Instead of 15s times 11.5, I used multiple!) Sorry for the mistake.
-- Danny (email@example.com), January 25, 1999.
I just ran the calculations too as the discussion was starting to confuse me! the equation I ran was (extention/focal length)squared= bellows factor. This gave me a factor of 11.67, for a time adjustment of 2.91 minutes (okay, round up to three minutes). there is still the reciprocity factor of the film to take into account, assuming you are using a kodak film, We now back up to what, 9 minutes? and if using color, filters to correct balance, so including that factor as well, we are back up to 11 or 12 minutes.
have you considered using strobe instead of hot lights?
-- Ellis (firstname.lastname@example.org), January 26, 1999.
Ellis has a point. I've just played with a meter, and the quoted exposure is about right for a 60W bulb at two feet from the watch. So a strobe, or a 250W bulb, or a few tablelamps would seem to be in order.
-- Alan Gibson (Alan.Gibson@technologist.com), January 26, 1999.
Hi Alan and Ellis,
Thanks for more suggestions. The reason that I don't want to use a strobe is because I don't want to make the photos look harsh, and uneven. Maybe Diffuser can help, but I don't want to take a risk on the expensive films and development. (I tried to take some pictures with my point-and-shoot digital camera with the flash, but the result scared me away. Too much relfections showed on the surfaces of the watch, both front and back.)
For now, I will try to use one and two lamps setup. I don't think that the reciprocity failure is a hugh problem here since it is acceptable for the films to expose within 15mins. I will try first and if the result is no good, then I will go out to central Park and take some photos of my watch on the bright sunny noon time. :)
-- Danny (email@example.com), January 26, 1999.
Back to film choice. Try Ektacrome EPN or Fuji Astia if you don't use tungsten. Both of these films stay neutral with longer exposures and don't go green like so many others do. In B&W, try TMax 100 whose reciprocity characteristics are very good. After about 15 seconds of exposure its reciprocity allows it to become faster than most 400 speed films on the market. One major help for you would be to learn how to light small objects. Light control will enable you to shoot the tabletop macro subjects with complete control and avoid overly long exposures. Try Ross Lowells excellent book "Matters of Light & Depth" for lighting info. Not a macro lighting book, it is one on the esthetics of light & should be very helpful.
-- Dan Smith (firstname.lastname@example.org), January 28, 1999.
>> The reason that I don't want to use a strobe is because I don't want to make the photos look harsh, and uneven. <<
i'm sorry i don't understand why the light will be harsh if strobe is used, use a softbox with more diffusion, tracing paper/butter paper or vellum is great, heck you could use a clean white cloth, use it really close to the subject in question, get clean highlights, flag it off to drop the highlight or whatever. if you don't have a softbox, make one. or simply use difffused flash, with the diffuser close to subject.
correct me someone if i'm wrong.
-- Jignesh Jhaveri (email@example.com), March 13, 1999.
Yes Dan, but EPN is a rather old type of film. New generation slide films perform mostly better in reciprocity. Most older films are not recommended above 10 seconds (colorshift indeed). Kodak always delivers reciprocity figures and filter corrections with their films. If not, I would take EPX (or -Z?) and start with 2 stops correction (+2 is for 100 seconds, but there's a logarithmic series involved here: 1, 10, 100, the next step would be 1000 seconds), so that would be 12 minutes. Half a stop down for bite in the slide: 9 minutes. No problem if there aren't any bees around.
-- Lot (firstname.lastname@example.org), March 13, 1999.
But Danny, you're right you can better use tungsten films.
-- Lot (email@example.com), March 14, 1999.