A1 ... questions

[frisky]

Does having a filter on (eg. UV) cause the pic quality to reduce?

i realize there are several diff measurements mentioned when it comes to filters. err ... what are the diff measurements avail?

"cir pol you probably need at least 62mm to avoid vignetting"
"49mm Size Standard Hoya thickness will not cause vignetting at 28mm"

how do we decide which 2 buy?

Anything in front of the glass do reduce quality. Of course if you are using a decent filter the difference is negligible, and it protects the lens from scratches and finger prints.

Normally you buy filter according to the filter thread in front of the lens you have. For 7hi & A1 this is 49mm. However, if you want to share filter between 2 lens of different filter thread diameter, then you buy according to the bigger filter thread. If you knows that there will be vignetting if you use a filter the same size as your lens thread, you'll want to get a bigger filter thread. How much bigger is a matter of trial and error (or by asking around).
To attached a bigger filter, you use a step up ring to convert the lens fitler thread to a bigger one.

Hope that helps.

 

[aong]

Hmm..... Then I guess either my HOYA UV is thicker than normal, or there has been some modification to the 7hi along the production line. Cos I changed to Minolta 49mm because I saw vignetting cause by the filter.

It does vignet using hoya filters at somewhere between 35 - 50mm (the lens does 'retreat' around this range)... happens on 7hi, 7i... not too sure on the dimage 7 tho' ;(

 

[ndroo-]

Anything in front of the glass do reduce quality. Of course if you are using a decent filter the difference is negligible, and it protects the lens from scratches and finger prints.

Normally you buy filter according to the filter thread in front of the lens you have. For 7hi & A1 this is 49mm. However, if you want to share filter between 2 lens of different filter thread diameter, then you buy according to the bigger filter thread. If you knows that there will be vignetting if you use a filter the same size as your lens thread, you'll want to get a bigger filter thread. How much bigger is a matter of trial and error (or by asking around).
To attached a bigger filter, you use a step up ring to convert the lens fitler thread to a bigger one.

Hope that helps.

anyone can tell me if i get a uv filter & cir col of 49mm, will there be vignetting? what else should i get/look out for (related to filters)?

 

[frisky]

anyone can tell me if i get a uv filter & cir col of 49mm, will there be vignetting? what else should i get/look out for (related to filters)?

If you stack, then certainly will get. If you use only one at a time, then depends on which brand/make you get.

 

[kelster]

hmm...my take on this...best is to take your camera to the shop..screw in the filters and check for vignetting on the spot before you buy the filter...guess its kindof the golden rule when buying any assessories for your cam...test it out on your equipment 1st lor...

 

[frisky]

hmm...my take on this...best is to take your camera to the shop..screw in the filters and check for vignetting on the spot before you buy the filter...guess its kindof the golden rule when buying any assessories for your cam...test it out on your equipment 1st lor...

Good idea, particularly for Digicam since you can see the result immediately, plus the A1 has 100% view finder......

But remember to check for different zoom position and range of aperature.