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200/4D Micro+SB28=dark slides?


benji

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I just received my new F4 200 micro D, my test shots with a F5 and

SB28 on a flash arm over the front of the lens shows I need to go +1.3

on a neutral subject to get a good exposure at around 1:1. Do you

have any ideas what might be wrong the only suggestion I have gotten

from nikon is to go straight TTL and not matrix on the flash. Why

didn't the camera warn me (blink) that there was under exposure at 0

ev.

 

This thing is driving me crazy and no one seems to know why my slides

(Fuji velvia) are dark. At 5.6 things do not look to dark but by f8,

11, 22 things are very dark. I did some test with Just TTL on the

flash but have little confidence that this is the problem, ( I don't

have them back yet). I was using Aperture priority and matrix on the

camera and making ev changes with the camera. My first test had the

zoom on the flash set at 18 and 20 with the diffuser this always

worked great with my 105D micro. They were dark as they also are at

all zoom settings on the flash including 85 which is the highest. I

just do not understand that sense the exposure is supposed to be taken

form the film plane why I am not getting the proper exposure. Why is

the flash being shut down to soon. It can't be that the flash is to

week as the proper exposure can be achieved at +1.3. If the adjustment

was only + or - .3 to .7 that would be understandable. Could there be

something wrong with the lens.

 

I hope someone can help.

 

Ben Czinski

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Just a thought . . . You don't say what your working distance is but when you deploy the diffuser (which is how you get the 18-20 zoom) you have to use the formula in the manual to figure out what the correct aperture is for that working distance. Are you using that? Have you noticed that the SB-28 indicates more underexposure the more you close down the aperture?
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Ben,

I have found the same problem as you, the only difference being that I use an N70 with the SB-28 and 200mm Micro Nikkor. In non-macro shots, exposures with no compensation in either TTL or matrix mode are generally fine. When shooting macro, I found slides are typically underexposed. This also happened with a Sigma 180 macro lens that I used before I got the Nikkor, so its not the lens. I routinely set the flash to 0.7-1.0 stops overexposure using straight flash at ratios above 1:4 or so, and if I use a diffuser or bounce attachment I'll sometimes add another +0.3 stops, and I always do macro flash photography in straight TTL mode, as I seem to get more consistent results than when in matrix. I don't get underexposure warnings until I stop down to about f16 or 22, depending on the reflectance of the subject and background, so it seems to me the problem is in the metering, not insufficient power from the flash. I've never understood how it works either in terms of the physics of the metering process; I've just learned to live with it. The important thing is that it consistently underexposes, so its easy to compensate and get consistently well exposed slides.

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Joe, one of the problems is that the sb 28 is not indicating any underexposure (blinking). It will blink in other situations say f/32 at 15 feet, but not at macro distances (19 to 24"). The slides, however do darken with smaller f/stops. As far as the chart goes at 19" inches I should shoot at f8 or as it says in fine print "smaller, such as f11". The chart seems to be trying to prevent overexposure which is of course the opposite problem I am having.

 

As Peter is having the same problem a new question might be are we the only ones. If this is the case then perhaps there is some kind of equipment problem. If it is the same for all then I will just have to dial in +1 to +1.3 for macro work. I would be very interested in hearing from people who have used the 200 4D micro and the SB28 flash for macro work around 1:1 to 1:3.

 

Thanks

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I use a 200/4 w/F5 and SB-28 on an RRS flash arm quite frequently and have had no problems with underexposure. When I'm using the flash as the main light, I turn Matrix flash off (but leave the camera in Matrix metering mode). This prevents the camera from trying to balance the flash against the ambient that I've intentially set to be 3-4 stops (or more) low. I set the flash and camera compensation to 0.0 and usually set flash bracketing at +/- 0.3 stops, just to get a choice of results. For fill flash I set the flash compensation to -1.3 stops and turn bracketing off.

 

Matrix fill flash works best for daylight fill at normal shooting distances.

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  • 2 years later...

The problem you describe is probably due to the fact that Nikon's 3-D metering system assumes that the flash is the same distance from the subject as the film plane. If the flash unit is closer to the subject, the matrix pre-flash "thinks" the subject is more reflective and reduces the exposure for the main flash. Setting the flash to regular TTL disables the pre-flash, and your exposures should turn out much better.<p>

It makes me wonder why we need the "D" chips in our macro lenses, though...

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