Camera asks for focal length each time?

Darius4522 · 10-03-2007, 10:43 PM

OK..I have an SMC Pentax A 70-210 f4 zoom, and get the confirm the focal length message also (not always, but sometimes).

What's best to insert? I understand insert the number for a prime lens, but what about a zoom? The tip on the green hexagonal was great, thanks, for I, too, had been using the red beeper!

Last edited by Darius4522; 10-03-2007 at 11:09 PM.

little laker · 10-04-2007, 08:23 AM

When I'm in the same boat I'll usually set it some where in the middle.

However if I'll mostly be shooting at 300mm I'll set it on 300, or 70mm I'll set it on 70.

JCSullivan · 10-04-2007, 10:01 AM

Ahaaaaaaaaaaa! Great questions. What if...

You're using 50mm + 1.4 or 1.7 TC

Thanks

**Lowell Goudge** · 10-04-2007, 10:08 AM

Originally posted by JCSullivan

Ahaaaaaaaaaaa! Great questions. What if...

You're using 50mm + 1.4 or 1.7 TC

Thanks

Simple,

If you are using a lens that does not feed focal length to the camera, just enter prime length times multiplication factor.

If you are using a lens that does feed focal length to the camera (I'll use my example Sigma APO 70-200 f2.8 EX DG plus 1.4x TC) you are out of luck, because the camera will NOT let you enter a correction for the focal length, This has an impact on performance of shake reduction. Pentax has been advised but no fix yet.

If you are using a zoom, and can enter the focal length, there are really 3 options, depending on why this is on the camera. You will normally have a preferred focal length, usually either maximum or minimum depending on the day. Just set it that way. If you are really shooting all over the place (in terms of focal length) set it to the middle.

Tom M · 10-04-2007, 11:36 AM

The Pentax manual clearly states that you should change the focal length to match the actual focal length you're shooting at. This means that, if you're shooting at 100mm, you should have the SR on 100mm.. If your next shot is at 85mm, you should change the value in the SR menu to 85mm, and so on.

Bascially, they are telling you that 'picking something in the middle' is not recommended.

**Lowell Goudge** · 10-04-2007, 02:00 PM

Originally posted by Tom M

The Pentax manual clearly states that you should change the focal length to match the actual focal length you're shooting at. This means that, if you're shooting at 100mm, you should have the SR on 100mm.. If your next shot is at 85mm, you should change the value in the SR menu to 85mm, and so on.

Bascially, they are telling you that 'picking something in the middle' is not recommended.

While I agree in principle, you may not have the luxury of time to look at th elens, look at the menu and set the focal length between shots. while middle is not optimum, what is worse, non optimum setting or no shot

Mike Cash · 10-05-2007, 06:40 AM

With a wide range like 70-200, I would guess that turning the SR off would be preferable to "something in the middle".

I must admit, though, that not really knowing the answer to this is one of the reasons I avoid the issue by not using zoom lenses.

Tom M · 10-05-2007, 09:53 AM

I completely agree with you Lowell, I just wanted to relay what the manual says to do. Even if it can be impractical at times.

Mike Cash, I would have to agree with what you say as well. Simply switching SR off and using a proper shutter speed is a simple solution. If SR use is in question, remove it from the equation. Problem solved.

For those that do wish to use SR and zoom lenses, do as the manual says and adjust the SR focal length to the ACTUAL focal length you are currently shooting at and adjust the SR to match the focal length each time you change your zoom level. No questions here, just a pain.

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10-03-2007, 10:43 PM	#16
Darius4522 Inactive Account Join Date: Jan 2007 Location: Adelaide, Australia Photos: Gallery Posts: 155	OK..I have an SMC Pentax A 70-210 f4 zoom, and get the confirm the focal length message also (not always, but sometimes). What's best to insert? I understand insert the number for a prime lens, but what about a zoom? The tip on the green hexagonal was great, thanks, for I, too, had been using the red beeper! Last edited by Darius4522; 10-03-2007 at 11:09 PM.

10-04-2007, 08:23 AM	#17
little laker Veteran Member Join Date: Sep 2006 Photos: Gallery Posts: 5,697	When I'm in the same boat I'll usually set it some where in the middle. However if I'll mostly be shooting at 300mm I'll set it on 300, or 70mm I'll set it on 70.

10-04-2007, 10:01 AM	#18
JCSullivan Veteran Member Join Date: Sep 2006 Location: Windsor, Canada Posts: 3,056	Ahaaaaaaaaaaa! Great questions. What if... You're using 50mm + 1.4 or 1.7 TC Thanks

10-04-2007, 10:08 AM	#19
Lowell Goudge Site Supporter Join Date: Jan 2007 Location: Toronto Photos: Gallery \| Albums Posts: 17,888	Originally posted by JCSullivan Ahaaaaaaaaaaa! Great questions. What if... You're using 50mm + 1.4 or 1.7 TC Thanks Simple, If you are using a lens that does not feed focal length to the camera, just enter prime length times multiplication factor. If you are using a lens that does feed focal length to the camera (I'll use my example Sigma APO 70-200 f2.8 EX DG plus 1.4x TC) you are out of luck, because the camera will NOT let you enter a correction for the focal length, This has an impact on performance of shake reduction. Pentax has been advised but no fix yet. If you are using a zoom, and can enter the focal length, there are really 3 options, depending on why this is on the camera. You will normally have a preferred focal length, usually either maximum or minimum depending on the day. Just set it that way. If you are really shooting all over the place (in terms of focal length) set it to the middle.

10-04-2007, 11:36 AM	#20
Tom M Veteran Member Join Date: Aug 2007 Location: Lincoln Park, NJ Photos: Gallery Posts: 780	The Pentax manual clearly states that you should change the focal length to match the actual focal length you're shooting at. This means that, if you're shooting at 100mm, you should have the SR on 100mm.. If your next shot is at 85mm, you should change the value in the SR menu to 85mm, and so on. Bascially, they are telling you that 'picking something in the middle' is not recommended.

10-04-2007, 02:00 PM	#21
Lowell Goudge Site Supporter Join Date: Jan 2007 Location: Toronto Photos: Gallery \| Albums Posts: 17,888	Originally posted by Tom M The Pentax manual clearly states that you should change the focal length to match the actual focal length you're shooting at. This means that, if you're shooting at 100mm, you should have the SR on 100mm.. If your next shot is at 85mm, you should change the value in the SR menu to 85mm, and so on. Bascially, they are telling you that 'picking something in the middle' is not recommended. While I agree in principle, you may not have the luxury of time to look at th elens, look at the menu and set the focal length between shots. while middle is not optimum, what is worse, non optimum setting or no shot

10-05-2007, 06:40 AM	#22
Mike Cash Veteran Member Join Date: Jan 2007 Location: Japan Photos: Gallery Posts: 6,950	With a wide range like 70-200, I would guess that turning the SR off would be preferable to "something in the middle". I must admit, though, that not really knowing the answer to this is one of the reasons I avoid the issue by not using zoom lenses.

10-05-2007, 09:53 AM	#23
Tom M Veteran Member Join Date: Aug 2007 Location: Lincoln Park, NJ Photos: Gallery Posts: 780	I completely agree with you Lowell, I just wanted to relay what the manual says to do. Even if it can be impractical at times. Mike Cash, I would have to agree with what you say as well. Simply switching SR off and using a proper shutter speed is a simple solution. If SR use is in question, remove it from the equation. Problem solved. For those that do wish to use SR and zoom lenses, do as the manual says and adjust the SR focal length to the ACTUAL focal length you are currently shooting at and adjust the SR to match the focal length each time you change your zoom level. No questions here, just a pain.