Long lens useage? (Page 2): Whenever using a long lens, even with IS it is preferable if not on a tripod to use a high shutter speed, specially with a high ISO setting. This is most...

camerapapi Loc: Miami, Fl.

Whenever using a long lens, even with IS it is preferable if not on a tripod to use a high shutter speed, specially with a high ISO setting. This is most important if hand holding the camera.

Blurryeyed Loc: NC Mountains.

When you say that the camera was set at 100, I assume that you are talking about ISO, which is a bit low for birding with a long lens, remember fast shutter speeds are your friend with a long lens. High ISO's introduce noise that is true, you will have to find a balance.

Bobcat87

bobmcculloch wrote:

1 over the focal length is a rule for full frame, APS-C would be 1/125 for a 70mm focal length.

I am a relatively new DSLR (Nikon D5600) user and have heard the "1 over focal length rule", but have not heard that this doesn't apply to cameras that aren't full frame. Could you explain the formula you used for your comment. Thank you for the help.

CHG_CANON Loc: the Windy City

Bobcat87 wrote:

I am a relatively new DSLR (Nikon D5600) user and have heard the "1 over focal length rule", but have not heard that this doesn't apply to cameras that aren't full frame. Could you explain the formula you used for your comment. Thank you for the help.

Sometimes, google is your friend .... You've even quoted the appropriate search term: 1 over focal length rule

Most any of the results will give the details, such as https://photographylife.com/what-is-reciprocal-rule-in-photography . Within the discussion, your specific question is address under heading = Effective Focal Length

CHG_CANON Loc: the Windy City

John K wrote:

Trying to keep focus using a Tele lens 70mm-300mm. Seems I have a focus problem? Should a lesser lens size be better and not have to much camera shake using held option. The camera was on Auto focus, and set at 100 with sunny sky's.

This is a case where an example image in tantalizingly close to helping us help you ... if possible, please reply and store the original so all the details of the image can be obtained.

Blurryeyed Loc: NC Mountains.

Bobcat87 wrote:

I am a relatively new DSLR (Nikon D5600) user and have heard the "1 over focal length rule", but have not heard that this doesn't apply to cameras that aren't full frame. Could you explain the formula you used for your comment. Thank you for the help.

There are those who subscribe to the effective focal length rule, if you put a 100mm lens on a APS-C camera with a 1.5X crop factor that lens effectively becomes a 150mm lens. To me the formula does not actually make a lot of sense because the decrease in the angle of view is simply the effect of the decrease of the real estate of the sensor.

I shoot a Canon 5DSR, a 50mp sensor, If I were the APS-C mode on that camera is about the same as an 18mp APS-C camera or the old Canon 7D. So, should I used different calculations when shooting different modes? I think not, I think that it is true however that as the pixel density becomes greater, smaller pixels, the effects of motion blur becomes more evident so you have to use more care.

Bobcat87

CHG_CANON wrote:

Sometimes, google is your friend .... You've even quoted the appropriate search term: 1 over focal length rule

Most any of the results will give the details, such as https://photographylife.com/what-is-reciprocal-rule-in-photography . Within the discussion, your specific question is address under heading = Effective Focal Length

Thank you. I now know to look for the term, "Effective Focal Length" and will look that up.

bobmcculloch Loc: NYC, NY

Bobcat87 wrote:

I am a relatively new DSLR (Nikon D5600) user and have heard the "1 over focal length rule", but have not heard that this doesn't apply to cameras that aren't full frame. Could you explain the formula you used for your comment. Thank you for the help.

The crop sensor creates an effective focal length of apx 1.5 times the actual focal length, magnifying both the image and any vibration.

Bobcat87

Blurryeyed wrote:

There are those who subscribe to the effective foc... (show quote)

Thank you. This info gave me some additional info about APS-C which helped me do additional research.

dsmeltz Loc: Philadelphia

John K wrote:

Trying to keep focus using a Tele lens 70mm-300mm. Seems I have a focus problem? Should a lesser lens size be better and not have to much camera shake using held option. The camera was on Auto focus, and set at 100 with sunny sky's.

Need more information to provide any useful help. Please repost photo with store original. Is this the full original photo? I mean is this a crop of the original photo? Did you use a tripod? What were your settings? Is the 100 shutter speed or ISO?. Were you at 300mm? What was your shutter speed?

Bobcat87

bobmcculloch wrote:

The crop sensor creates an effective focal length of apx 1.5 times the actual focal length, magnifying both the image and any vibration.

Thank you for your concise reply. It, along with CHG_CANON's, lead me to the photography life website, which explained it at a level that I can digest. I really appreciate the help from you Hogs!

Bobcat87

CHG_CANON wrote:

Sometimes, google is your friend .... You've even quoted the appropriate search term: 1 over focal length rule

Most any of the results will give the details, such as https://photographylife.com/what-is-reciprocal-rule-in-photography . Within the discussion, your specific question is address under heading = Effective Focal Length

Thanks so much! That website explained it very well, along with exceptions.

Blurryeyed Loc: NC Mountains.

bobmcculloch wrote:

The crop sensor creates an effective focal length of apx 1.5 times the actual focal length, magnifying both the image and any vibration.

So, how does that work with the newer high density sensors like the 5DSR or the D850, I believe that these cameras have both full frame mode and crop frame mode, I know that the Canon does, does the calculation change when the mode changes? I think not, it has a lot to do with the density of the pixels and the sharpness of that sensor.

agillot

try hand focus , also watch for shake / motion / camera speed .

dsmeltz Loc: Philadelphia

The OP, John K, seems to have disappeared.