Interpreting polaroids & sharpness question

Up until a few weeks back I was under the impression

that a polaroid back would be a very useful

addition to my equipment. So, for a wedding, I rented

a brand new Hasselblad PolaPlus magazine (I was the

first person to rent it).

 

Once I figured out how to pull out the film without

getting a weird shaded area on one quarter of the

image (beginners mistake...), the first disappointment

came: There was no sharpness in the image. It was

almost impossible to judge sharpness from the

polaroid. It gave some indication of where the lens

was focused but even that was very hard to determine.

I used a Polaroid ISO 100 colour film.

 

The second disappointment was that it was very difficult

to fine tune the flash setup using the polaroids. The

information was just not there in the image to enable

me to draw any intelligent conclusions (as opposed to

the information on a contact sheet from ordinary

film).

 

Now, if this is how polaroid images look, are they

really of any help to anyone? Personally, using my

handheld meter and comparing ambient light to

the flash readings gave me much more information than

was obtainable from the polaroid images! Perhaps

because I'm experienced using this method.

 

Are polaroids only helpful to avoid blatant exposure

errors and not of any help for fine tuning? How do

you use polaroids and how do you interpret them?

 

Thanks for reading this long winded question.

Peter,

 

I can appreciate your disappointment with the Polaroid back. my experience of them has been a bit more positive and I find it a very useful tool.

 

Most of my work is studio black and white portraits using hotlights (domestic grade floods and arrays of smaller lights)with high speed (ISO 3200) film. The polaroid back give me the freedom to paint with light, instead of having to wait until the proof sheet phase to see the results.

 

The other use is taking pictures of strangers, ask to take a photo of a stranger and often they say no. Offer to give them a polaroid and the answer can often be different.

 

Polaroid backs can spot obvious exposure errors and allow some limited fine tuning, even with the B&W polaroid which appears much sharper than the colour version, the fine focus capability is limited.

 

A great creative tool for the studio. Not so good on the run IMHO.

 

Regards,

Hi Peter!

 

I felt the same disappointment when I first used a polaroid for a job. But I overcame this when I changed my thinking, and that was: "polaroids are what you see is what you get" for whatever film that you use. Not true!

 

Polaroid is there to guide us, not to be dependent on it. You have to calibrate your polaroid to your system and supplies.

 

An instant film has a different response in terms of color, tonality or sensitivity (no matter how small) compared to a tranny or a neg. Even two brands of color film will render the colors of the same scene differently, no matter how trivial the difference is. So why should we expect an instant film to precisely reflect what will come out out of different brands of trannies or negative films?

 

What I did...I did a test shoot for the instant film brand I use (Fuji FP100C asa 100) and the film I frequently use on a typical job in the studio (Provia100F asa 100) using the camera I always use (RB67 180mm lens) and the studio lights I always use, metering with a flash/exposure meter that again I always use. Get the point here? Minimize variables.

 

For the test shoot, I got a color patch (you could borrow one from a printing press or from a minilab), lit it with the studio lights in the studio and metered it in incident mode. I then made an instant film exposure using the incident reading. I made a few more at -1, -2, -3, -4 and +1, +2, +3 and +4 stops (get plenty of polaroids and better if you can make the increment by 1/2 stop). Then, I took a shot of the color patch, this time using a positive film at an exposure setting determined by my exposure/flash meter (assuming your meter, camera and the film you are using are calibrated already).

 

Have the film processed and compare the results with the different polaroid exposure settings you made. At the metered setting, my polaroid output was 1/2 stop darker compared to the tranny.

 

Remembering this, each time I make a polaroid exposure, I just visualize that my film output will be 1/2 stop brighter based on the polaroid image. Possibly, this is no longer true if I use a different lens (different shutter), or a different brand of positive film, or a different brand of instant film.

 

You should not only check the overall exposure level. You should also observe how your particular brand of instant film renders shadow and highlight details compared to the positive or negative film that you usually use, to give you an idea how your polaroid image will translate into the final film. Don't forget the color balance as well.

 

I hope my experience will be beneficial to you. Yes. The polaroid is a very useful tool. It removes my anxiety and worries between shoot and waiting for the film to get processed.

 

jayalonzo@edsamail.com.ph

If you want to check sharpness, use pos/neg type 665. The negative is <i>very</i> sharp. You will need water to wash the black backing off and a loupe to see the grain. Use your flash meter to determine correct exposure, and test to match Polaroid EV to "real" film. For instance, I rate ProVivid at iso 200, so RDP2 and RAP are one stop open from a good looking 689. Polaroids are very handy for checking composition, shadow and light position and errant reflections that modeling lamps just don't convey.

You can use Polaroids for "large-tuning" your exposure, but not for fine-tuning it. The exposure depends too much on the temperature; unless you have a thermometer you can only make "gut-feeling" adustments to your exposure compensation and the time needed to develop the polaroid.

 

An addendum to Tom's advice:

If you can't clear the negative of 665 p/n film because you're in the field, don't worry. The prints from properly exposed type 665 p/n film are also very sharp. The difference in sharpness between this print and 667, 679, or 669 is night and day. Expose this film at 80-100 for the print.

A Polaroid back should NEVER be used to evaluate sharpness

since the film plane of Polaroud film lies at a totally different

position then roll film and the ground glass is positioned for roll

film not for the inside of a Polaroid pack sheet.

As a sidelight to the excellent answers above, the other day I was reading about a very well paid female photograper in New York. Her field is advertising photography and she's very good at it. I believe she said she uses Nikons in the field, maybe in the studio too. Any way, this lady uses her light meters to get her basic setup, but then shoots quite a few Poloroids to "fine tune" the lighting the way she wants it, never basing the final photo on the meter readings alone. I sometimes use a polaroid back on my RB to help in adjusting lights, since I have a hard time "seeing" my lighting ratios. I don't pay much attention to the Polaroids sharpness. It's been useful to me in that respect.

Bob, I regularly see sharp Polaroid proofs, and it seems to be because the folks who manufacture the backs do a pretty good job of making sure the pack ends up at the film plane (or vice versa). Now it may well be true that trying to evaluate a Polaroid proof for sharpness with a 10x loupe is a pointless waste of time, but when Peter says "there was no sharpness in the image", that's a pretty good clue that something was wrong, either with the back or how he was using it.

 

If I shoot a Polaroid with my Mamiya RB67, whatever was in focus in the viewfinder will be visibly sharp on the print. If that's not the result he got, then something is wrong. Hasselblad claims that the results with this back should be sharp enough for enlargements if you use Type 665 pos/neg film; if they're not lying in a blatantly actionable way, that should make it plenty sharp enough for a contact print.

I have printed 20x24 from my Polaroid 665 negs made on an RB67 Pro S and 4x5 type 55 made with Linhof. Up to 11x14 with the Hasselblad and NPC back. There was excellent sharpness in all cases. The film plane is the film plane is the film plane... I am, however, skeptical of the Hasselblad Polaroid backs with a sheet of glass in them, that's why I use the NPC... t

Polaroid proofs can never match the sharpness of a good roll of

film. They are only meant as a preview of your image for general

lighting and composition. They are great tools when working

with art directors who do not like looking thru viewfinders or

serve as quick comping images for art directors to lay over page

layouts.

 

The only Polaroid film that is sharp is the type 55 or 665, that is

because it IS actually film. A poduct photographer friend of mine

shoots tyep 55 or 665 and checks it the neg with a loupe to

determine ultimate sharpness prior to making exposures.

"Bob, I regularly see sharp Polaroid proofs, and it seems to be

because the folks who manufacture the backs do a pretty good

job of making sure the pack ends up at the film plane (or vice

versa). Now it may well be true that trying to evaluate a Polaroid

proof for sharpness with a 10x loupe is a pointless waste of

time, but when Peter says "there was no sharpness in the

image", that's a pretty good clue that something was wrong,

either with the back or how he was using it. "

 

Not really. The back simply can't, on its' own position the

Polaroid film at the film plane as the film is inside the cartridge.

 

Since depth of focus is greater with longer lenses the longer the

focal length the less likely softness would be a problem and the

shorter the more likely.

 

In order to try to eliminate this problem other means have been

adapted by some manufacturers to correct the film plane

discrepency with polaroid.

 

For instance Hasselblad mounts a glass plate in their Polaroid

back which shifts the focus a distance equal to 1/3rd the

thickness of the plate to compensate the different film plane.

 

Unfortunatley most manufacturers do not take this step.

<blockquote><i>Not really. The back simply can't, on its' own position the Polaroid film at the film plane as the film is inside the cartridge</i></blockquote>

 

<p>In other words, you were making a generalization based on the limitations of some back designs, which does not happen to apply to the specific back mentioned in the question (nor to the one I use on my RB67, the ones we all use on 4x5, any of the NPC backs, etc...).

 

<p>Polaroid backs can be and <i>are</i> sharp on many cameras, Bob, and the model mentioned in the question is one that specifically advertises sharpness as a feature, one which you agree goes to some lengths to correct for the different distance to the film plane.

 

<p>Given that we're all agreed that you have to compensate in some fashion <i>if you can't position the pack at the normal film plane</i>, and given that the back in question does, in fact, take steps to compensate, what does the phrase "there was no sharpness in the image" imply? From here, it looks an awful lot like either "defective product" or "pilot error"; the only other choice is "deliberate fraud by the manufacturer", and even you don't seem to think that's likely.

 

<p>Now, given the two most likely options, how do we help Peter determine which it was? Since it was brand new and he was the first renter, I'm inclined to think it may have been defective, something that could be tested by attaching it to some of the store's cameras and making test shots under controlled conditions (this is obviously in their interest as well).

Thank you all for contributing and making this a

very interesting discussion. My first time usage

of the polaplus back could indeed be the cause of

the unsharp results but perhaps I was just expecting

too much... I expected the sharpness to be similar

to what one gets when having a photo made for

passports or ID-cards on polaroid material. I exptected

that with my tripod mounted Hasselblad I would at

least achieve sharpness as good as or better than what

I used to get from my Polaroid camera that I used to

own in the early 1980's. But that was not the case.

And that simple camera costed me the equivalent of

25-30$.

 

As for handling I expected the back to mount similarly

to an ordinary film back and attached it as such.

Perhaps this was wrong and I should have studied the

instruction manual more carefully. But since there was

no light leakage (spelling?) visible on prints I assumed I had mounted the

back the correct way.

 

From your answers I'm leaning towards the conclusion that

I just expected too much of the material and that it could

be of some use if used with the thoughtful approaches as

are expressed in several of the contributions above.

 

Funny though, a camera for 30 dollars giving better sharpness

than a Hasselblad on polaroid colour film...

"In other words, you were making a generalization based on the

limitations of some back designs, which does not happen to

apply to the specific back mentioned in the question (nor to the

one I use on my RB67, the ones we all use on 4x5, any of the

NPC backs, etc...). "

 

All Polaroid backs for all format cameras are made by Polaroid

and sold to camera manufacturers, and 3rd party manufactures.

 

All the camera manufacturers and 3rd party manufacturers do is

add their connector for their camera body and other frill and

features (glass plate on Hasselblad for instance).

 

In other words the inside of all medium format Polaroid backs

are identical as far as film positioning.

<blockquote><i>In other words the inside of all medium format Polaroid backs are identical as far as film positioning.</i></blockquote>

 

<p>Bob, I'm sure someone out there didn't know that Polaroid made the guts of all the Polaroid backs out there, but as information relevant to the original question goes, it was pretty darn useless. You've never seen an MF Polaroid proof come out sharp? Fine; others have, and I suspect there are more of us than there are of you. It's interesting to note that I've <i>never</i> seen your little caveat mentioned in any of the many books that recommends using Polaroids for proofing; I just looked again through a half-dozen of the best books on my shelf, and it ain't there.

 

<p>Bottom line, there is no reason why Peter shouldn't have gotten prints at least as sharp as from the $25 Polaroid camera he had 20 years ago. Indeed, they probably should have been <i>better</i>, since he had a nice piece of Hasselblad glass in front.

My 2 cents worth on this old thread.

 

Using a pola back on an RZ67 II the test prints seem like a decent way to check general lighting, depth of field, composition, etc. But, it seems to me, that the polaroid is a poor way to check sharpness (or color). They lack the detail needed to do this (B&W seem sharper than the color). I just reviewed my test prints and the matching transparencies. The transparencies are sharp, very sharp. I can see every strand of the model's hair and every eyelash. When I look at the polaroid test prints, well, they aren't fuzzy but if I got back transparencies that looked as soft as the test prints I'd be pretty pissed.

 

Perhaps it's problems with the back I'm using. That said, I'd say looking through the viewfinder is a thousand times better for judging sharpness/focus.

 

I guess I'd like to know if any of the defenders of the sharpness of Polaroid test prints actually use them to check sharpness.