Blur at F-40......... (Page 2): You're using f40 (forty) or f4.0 (four point zero)? What lens has an f40 setting? Just curious Thanks...

twowindsbear

You're using f40 (forty) or f4.0 (four point zero)? What lens has an f40 setting?

Just curious

Thanks

Indi Loc: L. I., NY, Palm Beach Cty when it's cold.

twowindsbear wrote:

You're using f40 (forty) or f4.0 (four point zero)? What lens has an f40 setting?

Just curious

Thanks

It's in the camera. I took some pictures the other day for MWAC's lesson using my 50mm, f/1.8 but I was able to set my aperture to f/16 in-camera. I believe my camera can go down to f/32.
So, as you point out, it might be a typo, or they have a really expensive camera.

Archy Loc: Lake Hamilton, Florida

Indi wrote:

So you were submitting it as part of the assignment?

In a way...yes............

Archy Loc: Lake Hamilton, Florida

greymule wrote:

Archy wrote:

Taken at F-40...SS-1/8...ISO-400...focal length 180 on AV setting using a tripodcan anyone tell me what is causing the blur.

At high f-stops, there is a phenomenon called circles of confusion.

Here's an explanation:

http://www.luminous-landscape.com/essays/bokeh.shtml

Thank you............

Indi Loc: L. I., NY, Palm Beach Cty when it's cold.

greymule wrote:

Archy wrote:

Taken at F-40...SS-1/8...ISO-400...focal length 180 on AV setting using a tripodcan anyone tell me what is causing the blur.

At high f-stops, there is a phenomenon called circles of confusion.

Here's an explanation:

http://www.luminous-landscape.com/essays/bokeh.shtml

Thanks for that info. It explains a lot.

Archy Loc: Lake Hamilton, Florida

Indi wrote:

twowindsbear wrote:

You're using f40 (forty) or f4.0 (four point zero)? What lens has an f40 setting?

Just curious

Thanks

It's in the camera. I took some pictures the other day for MWAC's lesson using my 50mm, f/1.8 but I was able to set my aperture to f/16 in-camera. I believe my camera can go down to f/32.
So, as you point out, it might be a typo, or they have a really expensive camera.

In AV mode my Pentax Kx can attain f-40...but the lens only goes to f-32...perhaps the camera and lens are fighting one another at f-40...go figure..........

Archy Loc: Lake Hamilton, Florida

twowindsbear wrote:

You're using f40 (forty) or f4.0 (four point zero)? What lens has an f40 setting?

Just curious

Thanks

The camera set in AV mode can get to f-40...but the lens only goes to f-32...perhaps that is the problem...with the camera set in AV mode and the camera set at f-32 there is no problem with blur........

CAM1017 Loc: Chiloquin, Oregon

Archy wrote:

Taken at F-40...SS-1/8...ISO-400...focal length 180 on AV setting using a tripodcan anyone tell me what is causing the blur.

If you really took it at f-40 (Don't think most lens close down to this) & SS 1/8 I would open the lens up to around F-11 to get a much faster shutter speed. This might reduce possible movement. This assumes you are within the focus range of your len.

Archy Loc: Lake Hamilton, Florida

CAM1017 wrote:

Archy wrote:

Taken at F-40...SS-1/8...ISO-400...focal length 180 on AV setting using a tripodcan anyone tell me what is causing the blur.

If you really took it at f-40 (Don't think most lens close down to this) & SS 1/8 I would open the lens up to around F-11 to get a much faster shutter speed. This might reduce possible movement. This assumes you are within the focus range of your len.

I think I have it figured out with all the help of yall on UHHI was trying to force my lens to do something it cant doThank y'all again.

twowindsbear

Archy wrote:

quote=CAM1017 quote=Archy Taken at F-40...SS-1/8... (show quote)

What was your conclusion? What do you plan to change when you make that shot again?

Archy Loc: Lake Hamilton, Florida

twowindsbear wrote:

quote=Archy quote=CAM1017 quote=Archy Taken at ... (show quote)

#1 conclusionI aint as smart as I thought I wasimagine that
#2 conclusionmy camera on AV mode can reach f-40....
#3 conclusionthe lens can only reach f-32....
#4 conclusionwith the camera in AV mode and on f-32 and the lens being able to handle f-32 every was fine....
Final conclusiondont try to make a lens do more than it can deliver and I plan to shoot from f-4 to f-22no more f-40...

Archy Loc: Lake Hamilton, Florida

Here are some test shots...same camera Pentax Kx in AV mode set at f-32...same lens Tamron 70-300 lowest f-stopf-32...second shot is at f-16........

f-32...SS 1/25...ISO 200...focal length 100mm

f-16...SS 1/100...ISO 200...focal length 100mm

CAM1017 Loc: Chiloquin, Oregon

Archy wrote:

Here are some test shots...same camera Pentax Kx in AV mode set at f-32...same lens Tamron 70-300 lowest f-stopf-32...second shot is at f-16........

Good job! The second looks sharper to me. Generally a lens closed all the way down to F32 does not have its best optical properties. Mid range at F16 it would be better. You may be able to check on line with Tamron to see what your lens does at different F setting. These charts may give you a better perspective on where to set your aperture. :thumbup:

Archy Loc: Lake Hamilton, Florida

CAM1017 wrote:

quote=Archy Here are some test shots...same camer... (show quote)

Yes the second one is a wee bit sharper and thank you for your help :thumbup:...I will check on the Tamron thing............

GoofyNewfie Loc: Kansas City

Indi wrote:

Why not try manual, and a lower f-stop to get a bokeh? The image seems like it's a little dark. The lack of sufficient light might be preventing you from getting sharp focus. Probably because your aperture is high @ f-22.
Just some thoughts.

Bokeh is not the same as shallow depth of field.
Bokeh refers to the quality of the out of focus areas, specifically visible in the highlights.

Small apertures can cause someting called diffraction, which reduces the sharpness of the image.