Flash + bounce card + Fuji XTra 800 + sharpness


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TME

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Jan 19, 2002
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Clementi
Hi,

I posted some time ago regarding use of a bounce card. I did a test under low light conditions using a Dynax 7 + 5600HS + a bounce card (home made by Sulhan). Now I need some help in evaluating the aftermath...... :D

Equipment:
Minolta Dynax 7
Tamron 24-135mm SP f/3.5-5.6
Minolta 5600HS flash
On all shots A priority at f/5.6 and shutter speed was constant at 1/60 sec. Centre weighted metering.

I shot one roll Fuji XTra 800 no compensation whatsoever with the bounce card, flash head at 45 degrees. The pictures turned out a little soft. Why? The softness is noticeable but

I shot another roll Fuji XTra 400 with +0.7EV and -0.5 flash for some shots. I did not use the bounce card but fired the flash straight on. The pictures were pin sharp.

The ballroom was rather dark most of the time. It was really quite dark, most of the time I could see the IR pattern painted by my flash through the viewfinder on the subject.

Why the discrepancy? Did the bounce card cut the flash output so much that it affected the sharpness? How is sharpness affected by the flash output? I find it rather puzzling....
 

What was your focal length?
It appears that the softness is due to your handholding.

When you use bounced flash, the contribution of the flash exposure is less significant, hence you do not get as much motion stopping as a flash fired direct.

If the bounced flash light is really soft, you might even have to go back to the 1/focal length rule.
 

BTW, did you compare same focal length, same subject or just a variety of miscellaneous shots?
 

A very wide variety but mainly people posing for me. It was a staff dinner. My focal lengths also varied greatly but did not exceed 80mm most of the time. Mainly between 28-50mm. Anyway the entire roll was soft except for shots where the flash blew out the subjects (I was too close I guess even with the bounce card)

Motion stopping power of flash?? Woah! U lost me there... how does it work?

I also noticed that in some of my shots (ISO 800 roll), the prints were pushed. About 5 out of 36 exposures were push-printed. They had NNN1 or NNN2 printed behind. The others were NNNN. Do u know what they did? I noticed that the roll ISO800 had images that were a little duller compared to the other roll. I wonder if it was due to the bounced flash or due to the higher ISO? But there were no grains. It seems like a case of underexposure by about 1/2 - 2/3 stops (guesstimate).

I am thinking of doing my friend's wedding with direct flash -0.5 stop on the flash and +0.7EV on Fuji 400. That gave me outstanding results in terms of clarity, sharpness and colour saturation. But I do get hotspots... the bounce card seems to work pretty well without hotspots (at least highly muted). The effect is a lot more desirable but the shots seem underexposed. So I'm trying to find a balance that will give me what direct flash will without the hotspots..... some people's faces were very white due to direct flash..... perhaps I stood too close..... I did get some groups shots without the hotspots too..... I wonder why... maybe I was sufficiently far? I was on -0.5 flash exp when using direct flash.

The other thing is that on 1/60 shutter speed, the background was quite dark even on ISO800 film. Looks like I have to go down to 1/30. But interestingly on ISO400, the background was better but probably because I was shooting against a wall nearby so the was illuminated by the flash + direct flash as well. What u think? Any advice? 1/30 not very viable cos my hand shake is quite bad.
 

Actually I wish I could show u my shots and u critique the technical aspect of the shooting. My composition needs a lot more hardwork....... so that I also need advice for that aspect.....
 

TME said:
A very wide variety but mainly people posing for me. It was a staff dinner. My focal lengths also varied greatly but did not exceed 80mm most of the time. Mainly between 28-50mm. Anyway the entire roll was soft except for shots where the flash blew out the subjects
Note this. Your sharp shot come only from the ones with strong direct flash, this shows that your shutter speed was too low for your handholding/focal length.

Motion stopping power of flash?? Woah! U lost me there... how does it work?
Flash stops motion simply because it totally overwhelms any motion/shake captured within the ambient exposure. Think of how slow-sync works and you will get the idea.

I am thinking of doing my friend's wedding with direct flash -0.5 stop on the flash and +0.7EV on Fuji 400. That gave me outstanding results in terms of clarity, sharpness and colour saturation. But I do get hotspots... the bounce card seems to work pretty well without hotspots (at least highly muted). The effect is a lot more desirable but the shots seem underexposed. So I'm trying to find a balance that will give me what direct flash will without the hotspots..... some people's faces were very white due to direct flash..... perhaps I stood too close..... I did get some groups shots without the hotspots too..... I wonder why... maybe I was sufficiently far? I was on -0.5 flash exp when using direct flash.

The other thing is that on 1/60 shutter speed, the background was quite dark even on ISO800 film. Looks like I have to go down to 1/30. But interestingly on ISO400, the background was better but probably because I was shooting against a wall nearby so the was illuminated by the flash + direct flash as well. What u think? Any advice? 1/30 not very viable cos my hand shake is quite bad.
Try adding +EV to the bouncecard setting. Avoid going down to 1/30, dark backgrounds are a lot more acceptable than blurred shots. When in doubt, always play safe.
 

I have this problem before too. If you are using negatives, it could be that the image was probably UNDER-exposed and the lab correcting this under-exposure made the images look FUZZY due to a lack of detail on the negatives. If I do bounce photography, I use a high ISO (800 is good) and I tend to use large apertures like f4 and above. Lots of light is being lost when it is bounced. Take a look at the negatives of the sharp images and those of the soft images.

I guess they are not only soft, but muddy looking as well ? I had the same problem before.... argh... maddening.
 

Zerstorer said:
Note this. Your sharp shot come only from the ones with strong direct flash, this shows that your shutter speed was too low for your handholding/focal length.


Flash stops motion simply because it totally overwhelms any motion/shake captured within the ambient exposure. Think of how slow-sync works and you will get the idea.


Try adding +EV to the bouncecard setting. Avoid going down to 1/30, dark backgrounds are a lot more acceptable than blurred shots. When in doubt, always play safe.


But at 1/60sec at focal length less than 60mm should be ok what....... anyway even at that focal lengths still not enough light.

So u mean +0.3 to +0.7EV and then leave the flash power alone? I was thinking of +0.3EV and then +0.5 for flash. I will be experimenting next week again. I will be using a Lumiquest this time and vary with the bounce card as well.
 

TME said:
So u mean +0.3 to +0.7EV and then leave the flash power alone? I was thinking of +0.3EV and then +0.5 for flash. I will be experimenting next week again. I will be using a Lumiquest this time and vary with the bounce card as well.

I actually meant + flash EV, leave the ambient exposure as it is.

The shots that were soft, were they taken at the 135mm end or the 24mm end?
 

marcwang said:
I have this problem before too. If you are using negatives, it could be that the image was probably UNDER-exposed and the lab correcting this under-exposure made the images look FUZZY due to a lack of detail on the negatives. If I do bounce photography, I use a high ISO (800 is good) and I tend to use large apertures like f4 and above. Lots of light is being lost when it is bounced. Take a look at the negatives of the sharp images and those of the soft images.

I guess they are not only soft, but muddy looking as well ? I had the same problem before.... argh... maddening.


No the lab did not push the printing. The data at the back of the prints indicate NNNN for the entire roll except for 5 shots. So the exposure was ok. Only the background was underexposed (which is expected) but the subjects (faces)were all well lit. The clothes could be a little brighter. As I say the shots would probably look nicer with 1/3 or 1/2 stop more light. So I wouldn't say the shots were underexposed.

Anyway, my bouncing was confined to the bouncing off a card rather than off a wall. So I'm not sure if a lot of light was lost. But certainly it seems that the loss of light caused the underexposure by 1/3-1/2 stop. The negatives look ok, comparing with the other roll that was ok. The intensity of colour of the negatives is comparable. I was just wondering if pushing the flash to +0.5 would helpor maybe even +1.0...
 

Perhaps you could scan some of the shots?
 

Zerstorer said:
I actually meant + flash EV, leave the ambient exposure as it is.

The shots that were soft, were they taken at the 135mm end or the 24mm end?


Soft in all the focal range I used that night..... mainly between 28-50mm...... never used the telephoto end actually. I have used this lens extensively at all focal lengths and it always gives me pin-sharp images... this is the only roll where it actually gives me noticeably soft shots. Even my colleagues who are not photographers noticed it... although I think they noticed it after looking the other roll... it's acceptable on its own I guess...... without any reference...
 

junyang said:
Perhaps you could scan some of the shots?


That means I need to start a photo database. I have a webpage at Geocities which does not allow linking of images.... also scanning of prints not very good in my case as I use gloss prints.... they always turn out terrible when I scan them..... can I like upload to CS??
 

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