Honey, I underexposed the [print] film

[fino]

Can anyone give me a suggestion as to how I can correct this

problem. I accidentally underexposed a roll of Reala [iSO 100] by

not adjusting my exposure for a Polarizer filter that has a filter

factor of 2.3 to 2.8 [say 2.5]

 

What ISO should I get the lab to rate it as? The roll contains some

bright [i hope] landscapes and seascapes.

 

Any suggestions appreciated.

[art_haykin]

A 2.5 stop push on ISO 100 would be 600.

[justin_kern]

You are going to have a ton of exposure latitude with Reala, so you may be able to get away with pushing 1.5 or 2 stops plus some adjustment when printing. Hope this helps.

[m0002a]

Strangely enough filter factors are different than stops. A filter factor of 2 is 1 stop, a filter factor of 4 is 2 stops, a filter factor of 8 is 3 stops, etc.

[steve_s.]

Fintan, were you using an SLR? If so, you didn't underexpose the film because the in-camera light meter was reading light thru the filter. In that case, you wouldn't have to tell them to compensate at the lab, just have them develop the film normally. You would only have to compensate if you were using a TLR or rangefinder camera, or metering with a handheld meter, or otherwise not metering thru the lens and filter.

[patrick_ingram]

If you were using ttl metering, your exposure is ok (as mentioned above) as the meter was looking though the filter. Otherwise... a filter factor of 2.5 corresponds to 1.32 stops, not 2.5 stops. So go for a +1 and 1/3 stop push, or a film speed rating of 250 ISO (2.5 * 100).

[fino]

Sorry I should have mentioned that I was using a manual camera and a handheld meter so unfortunatly a TTL meter wont save me this time.

 

I came across this Filter Factor conversion table http://www.geocities.com/thombell/filterfactor.html

so I'm thinking of ISO 250 as sugested by Patrick Ingram, but I'll wait a few days and see any other suggestions.

 

Thanks for the replies.

[fino]

As sugested I rated as 250 ISO and they came out fine, thanks to all who posted and to Patrick Ingram.

 

Another happy customer!