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travischance
Sep-29-2009, 07:00 AM
I'm eager to purchase the Cokin system & have some questions. I'm reading that the P series is designed for threads up to 82mm but for focal lengths of 28mm and up. Would I experience vingetting with the P series or should I consider the X-PRO series instead (designed for focal lengths of 15mm)? My lens threads are as follows:

16-35 (82mm thread)
24-105 (77mm thread)
100-400 (77mm thread)

cmason
Sep-29-2009, 07:32 AM
i use P Cokin filters on my 77mm lenses, in the holder, without any problem. I don't have an 82mm to know, but I suspect it will be ok.

I don't think you will get any vignetting at all, perhaps that is the wrong word here. What you should be worried about is whether 1) the filter will cover the lens, and 2) the filter holder will be visible in the shot.

The filters are plenty big for 77mm, and likely for 82mm. However, I would worry that perhaps the filter holder itself may cause issues on the 16mm side, as it might be in the field of view and mess things up. However, he filter holder is not required, in fact, I never use it, I handhold the filters.

Miguel Delinquento
Sep-29-2009, 08:29 AM
Like CMason, I use the P series up to lens diameters of 77mm. I have not experienced vignetting at 12mm on a 77mm-sized 12-24mm lens.

I tried the lens holder (it came with the package) and gave up on it after 5 minutes. If you change lenses it is a basic hassle. I just hold the filter in front of the lens as needed. You have to do that with a graduated filter anyway.

I would not spend a lot of money on the system. I was able to buy a box of 40 filters and the holders for $25 used, so shop around. The Polarizer is pretty mediocre; most useful are ND filters. Lee makes similar and better filters if you want to go that direction. Besides Polarizer and ND filters, most of the other effects one can do with software.

M

travischance
Sep-29-2009, 09:36 AM
Do you remember where you purchased your set from? With fall just around the corner, at a minimum I'd like to have 1 GND filter. There is so much opportunity for great fall foilage shots in the DC area and several places with small lakes/ponds....

cmason
Sep-29-2009, 09:46 AM
Cokin filters are $10-$20 new, so while not as good a deal as above, they are no bank breaker

Miguel Delinquento
Sep-29-2009, 11:08 AM
Check Craigslist now and then. Post a wanted ad too. This is a typical item that takes up space on a shelf and folks forget about it without a trigger.

M

Do you remember where you purchased your set from? With fall just around the corner, at a minimum I'd like to have 1 GND filter. There is so much opportunity for great fall foilage shots in the DC area and several places with small lakes/ponds....

dlplumer
Sep-29-2009, 11:23 AM
On a crop sensor you should not experience any vignetting, but on a full frame you will with the wide angle.

If you plan on buying a 10-22 for your crop sensor, you will need the bigger cokin adaptor.

cmason
Sep-29-2009, 07:13 PM
On a crop sensor you should not experience any vignetting, but on a full frame you will with the wide angle.

If you plan on buying a 10-22 for your crop sensor, you will need the bigger cokin adaptor.

Sorry, but I just don't see how a filter will vignette. Vignetting is caused by a lens not being able to effectively focus the light against the entire sensor area, where it bends slightly at the edges (or severely in the case of a fisheye.) A filter modifies the light but does no focusing.

I can see where the edge of the filter cpuld come into view on a lens that extends beyond the edge of the filter, although since these are rectangular filters, typically the top and bottom of the filter will be visible and cause unpleasant artifacts.

ziggy53
Sep-30-2009, 06:09 AM
Sorry, but I just don't see how a filter will vignette. Vignetting is caused by a lens not being able to effectively focus the light against the entire sensor area, where it bends slightly at the edges (or severely in the case of a fisheye.) A filter modifies the light but does no focusing.

I can see where the edge of the filter cpuld come into view on a lens that extends beyond the edge of the filter, although since these are rectangular filters, typically the top and bottom of the filter will be visible and cause unpleasant artifacts.

The standard Cokin filter holder has 4 slots and can vignette very wide angle lenses. Cokin makes a special holder, the BPW400 Wide Angle Filter Hood for P Series, with a single slot specifically for those situations. Some people just buy an extra standard filter holder and cut off the outer slots.

http://www.bhphotovideo.com/c/product/628301-REG/Cokin_BPW400_BPW400_Wide_Angle_Filter.html

travischance
Sep-30-2009, 06:26 AM
This is the info I was hunting for. I want to eliminate the possibility of seeing the filter holder in my photos on the wide end. I have no intentions of purchasing the 10-22 as I have the 16-35 to suffice my wide angle needs. At the moment, I'm using and XSi and will upgrade to the 7D (once the reviews are out). Eventually I'll venture over to FF but not anywhere in the immediate future.

Craigslist is a great idea (only thought of Adorama, KEH & eBay) as is cutting off the outer slots on a second unit. What happens on those really bright days when you need to stack filters though? Thanks again!

ziggy53
Sep-30-2009, 08:19 AM
... What happens on those really bright days when you need to stack filters though? Thanks again!

The Cokin system is not able to cover all possibilities. If holding or taping multiple filters is not an option, a dedicated screw-in filter is probably indicated. There is also a method of using multiple photographs, stacked, to provide a sense of motion blur for water, etc.

http://pentaxdslrs.blogspot.com/2007/12/using-multiple-exposures-on-k10d.html

PS While that linked article relates to using a camera with a multiple exposure capability, you may also use software to combine multiple images:

http://blog.rrdphoto.com/2007/03/digital-multiple-exposures.html
http://www.naturephotographers.net/articles0903/tg0903-1.html

mdhtc
Oct-12-2009, 10:49 AM
Hi guys ...

I have Cokin filters, what is fstops and how to adjust fstop for each different filter.

Thanks ,,,,

ziggy53
Oct-12-2009, 12:05 PM
Hi guys ...

I have Cokin filters, what is fstops and how to adjust fstop for each different filter.

Thanks ,,,,

Mdhtc, welcome to the Digital Grin. :clap

It would be a tremendous help for us to understand your situation if we knew:

Which camera(s) you use?

Which Cokin filter(s)?