Pushing film with Minolta Cameras

Hi, I have both a 7000i and a 600si.

I only have one question regarding these two cameras....

If I was to uprate a 100 film to other speeds, purely for

experimental purposes, can I down rate the film back again to 100.

So fo example, with one roll of superia 100, could I take first frame

at 100, second frame uprated to 200, 3rd frame uprated to 400, 4th

frame uprated to 800 followed by the 5th frame back down to 100

again, and the remaining 29 frames contiued at 100.

I guess the only reason why I ask is if i wanted to uprate for one

frame mid film, can i then set the ISO back to default? ie 100 ?

Thanks

Paul

No!

The whole roll has to be shot at the same rating, and processed (developed) accordingly. Higher speed rating requires longer developing times (push), and lower rating, shorter times (pull).Only digital cameras are able to change the "iso rating" for individual frames.

Yes!

Of course you can - but why would you?. From a technical perspective, you can change the

settings as much as you'd like. There is nothing about these two cameras that would

prevent you from doing this.

However, if you push or pull, you need to stick with the same rating for the entire roll in

order for it to be properly developed. Otherwise, you will ruin your shots.

In short: Can you? Yes! Should you? No!

<I>I guess the only reason why I ask is if i wanted to uprate for one frame mid film, can i then set the ISO back to default? ie 100 ?<P>

No! The whole roll has to be shot at the same rating</I><P>

No, actually, you can shoot each frame at a different EI. No problem at all. If you process them the same, some will be under (or over) exposed.<P>

There is this misconception that under-exposing is the same as pushing. It's not. Pushing (and pulling) refer to a coordinated practice that involves changes in both exposure (EI) and processing (and yes, it can be done to some extent in C-41, E-6, K-14, and traditional B&W). If you have the film push- (or pull-) processed, some frame will be (more or less) correctly exposed and others over- (or under-) exposed--it's just that which frames will change.

So experiment away. However, I think you will find that C-41 film underexposed by more than 1 stop will look very bad, but can be overexposed by a stop or two and look okay.

Paul, a quick clarification of pushing film...basically what it means is that you underexpose your film in the camera and then you give longer development times so that your negatives come out looking basically normal but with some penalties to grain and shadow detail. It's something that you would want to do consistenly for the entire roll because you pretty much have to process the entire roll all at once. For example, when I'm in a situation where I need a faster film (like inside a dark building or museum), I shoot Tri-x (400 speed black and white film) at 1250 or 1600 and then give additional development to make up for the underexposure.

Now if you do what you described, going from 200, then 400, then 800, that just means that you will be underexposing by a stop, then 2 stops, and then 3 stops. If you then go back to 100 for the rest of the roll and have it developed normally, you'll just end up with most of your roll looking normal, and those particular frames looking underexposed.

I'll also add that pushing is more practical and useful for black and white and it seems like people routinely do it for slide film also although I have never shot slide film so I can't comment on that. But for color print film (c-41) it doesn't seem like something that is really worth it. Better just to get faster film.

Thanks guys. Maybe this should be in the film & processing forum....

I am now clear on this subject. The only reason why iasked was i hear of people uprating a film to obatin handhel speeds in dark places. If this was done mid roll, so halfthe roll is normal, hal pusehed to what criteria would the film be processed.

Thanks