Silly HD D FA 150-450mm question on zoom

crockpotveggies · 07-08-2019, 11:31 PM

So I got the beastly Pentax D FA 150-450mm AW zoom lens for my K-1 and did some test shots today. And I'm not sure if it's just me or if it's because I've now gone full frame, but the subjects I'm capturing seem to be much farther away than I'd expect at 450mm. When I look at photos on the Flickr group, they're beautifully framed and subjects are filling the photo. But the attached photo of a squirrel was only taken away at no more than 20 feet. At a focal length of 450mm I would have expected the subject to fill more of the frame. So is it just me getting used to FF format? Anyone have any suggestions? Part of the buying decision for this lens was so that I could remain farther away from the wildlife to not scare them.

Attached Images

View Picture EXIF

biz-engineer · 07-08-2019, 11:53 PM

Originally posted by crockpotveggies

When I look at photos on the Flickr group, they're beautifully framed and subjects are filling the photo.

Most are cropped. For subjects of 4 inches in size, to cover 1/3rd of the frame, the distance is 14 feet at 450mm. Sometimes in open spaces, I felt like being close enough, but when I measured the distance it was more than I initially thought (my experience).

crockpotveggies · 07-09-2019, 12:06 AM

Originally posted by biz-engineer

Most are cropped. For subjects of 4 inches in size, to cover 1/3rd of the frame, the distance is 14 feet at 450mm. Sometimes in open spaces, I felt like being close enough, but when I measured the distance it was more than I initially thought (my experience).

Good to know, I guess I should have expected some cropping. So it sounds like it's time for me to work on my stealth, as I think a lot of these critters will be quite fearful of this barrel!

LensBeginner · 07-09-2019, 12:30 AM

There's another factor - apart from crop factor and PP cropping - and that is the fact that focal length numbers are only true at infinity.
Generally, the closer you get to your subject, the "shorter" the FL becomes, due to the way the zoom and focusing works.
There were some threads about this WRT the 60-250, IIRC, where this phenomenon was quite apparent.
A picture of an oven was involved.

For instance:
https://www.pentaxforums.com/forums/10-pentax-slr-lens-discussion/369979-foc...-its-said.html

biz-engineer · 07-09-2019, 01:44 AM

Originally posted by crockpotveggies

o it sounds like it's time for me to work on my stealth, as I think a lot of these critters will be quite fearful of this barrel!

Wildlife react mostly on movement (movement of the hand trying to reach the grip and shutter). If I know when the animal is going to be, I install my DFA150450 K1 kit on a gimbal and operate it from a distance, using the IR remote dongle or using my phone with Image Sync., allowing the camera to be closer to subject.

derekkite · 07-09-2019, 05:33 AM - **1 Like**

Crop. Seriously crop. You will find the limits of the sensor density, your technique in keeping it sharp. To fill a 450mm screen with a squirrel means being really really close, and you get into another knarly problem of only it's nose being in focus.

Nice shot by the way.

zapp · 07-09-2019, 09:53 AM

Focal length is 450 mm. Distance is 6000 mm. Magnificationfactor is thus 13.
Frame is 24 mm in height, so you should fill the frame height with a 312 mm tall object. Squirrel covers 1/3 of the height, so it has 100 mm height or 4 inches. I don‘t think you have a problem. Maybe the distance was more like 30 feet... work on your technique and start cropping. 450 mm lens for small and shy objects is just the beginning.

**Apet-Sure** · 07-09-2019, 12:08 PM

Originally posted by crockpotveggies

And I'm not sure if it's just me or if it's because I've now gone full frame, but the subjects I'm capturing seem to be much farther away than I'd expect at 450mm.

How long have you had your K-1? Did you use an APS-C sensor camera previously? You may already be aware of this, but 450mm on APS-C gives you the same field of view as 675mm on full frame. Conversely, 450mm on full frame gives you the same field of view as 300mm on APS-C. So, switching from a smaller sensor to a bigger sensor will make subjects seem farther away for any given focal length lens.

crockpotveggies · 07-09-2019, 03:53 PM

Originally posted by Apet-Sure

How long have you had your K-1? Did you use an APS-C sensor camera previously? You may already be aware of this, but 450mm on APS-C gives you the same field of view as 675mm on full frame. Conversely, 450mm on full frame gives you the same field of view as 300mm on APS-C. So, switching from a smaller sensor to a bigger sensor will make subjects seem farther away for any given focal length lens.

It's only been a week on the K-1 so I'm still adjusting to full frame. Amazing, that's quite a difference between the sensor formats. Certainly explains why I'm experiencing this.

**aslyfox** · 07-09-2019, 04:52 PM - **1 Like**

Originally posted by Apet-Sure

How long have you had your K-1? Did you use an APS-C sensor camera previously? You may already be aware of this, but 450mm on APS-C gives you the same field of view as 675mm on full frame. Conversely, 450mm on full frame gives you the same field of view as 300mm on APS-C. So, switching from a smaller sensor to a bigger sensor will make subjects seem farther away for any given focal length lens.

this article and chart might help

Crop Factor Explained

**clickclick** · 07-09-2019, 05:27 PM

Originally posted by crockpotveggies

It's only been a week on the K-1 so I'm still adjusting to full frame. Amazing, that's quite a difference between the sensor formats. Certainly explains why I'm experiencing this.

What were you shooting with before the K-1?

**catfishjohn** · 07-09-2019, 05:51 PM

I very often use the 1.4 with my 150-450. It gives more reach with little to no loss of IQ. There is an article on the forum which covers the pair in detail. Want even more? Just pair with a KP or K70. Using really long focal length comes with a whole new set of problems so there is a learning curve.

**aslyfox** · 07-09-2019, 06:11 PM - **1 Like**

Testing the HD Pentax-DA 1.4x Teleconverter with the D FA 150-450mm on Full Frame

Read more at: Testing the HD Pentax-DA 1.4x Teleconverter with the D FA 150-450mm on Full Frame Review - Introduction | PentaxForums.com Reviews

" The Bottom Line
Using the HD Pentax-DA 1.4x AW AF with the HD D FA 150-450mm yields an impressive effective maximum focal length. Optical performance remains comparable to that of the lens alone. The pair cannot be used in full frame mode but, apart from that, there is nothing to stop users from pairing the two. "

Read more at: https://www.pentaxforums.com/reviews/da-14x-teleconverter-150-450mm-fullfram...#ixzz5tEVDUw5u

crockpotveggies · 07-09-2019, 07:44 PM

Thanks for that review! I actually just ordered the new 1.4x rear converter. It shows up tomorrow I'm quite excited to test it out. Should be great for birding.

**david94903** · 07-09-2019, 11:12 PM

I shoot a lot with the D-FA 150-450 on my K-1, and I crop my images a lot to get the final image I want. You can see many of my "cropped" images on my Flickr page. I'm rarely 20' away from my subject, usually more like 50' to 100' on average, and often further. And you'll quickly discover that the K-1 will offer excellent cropping opportunities that weren't even possible with any of your previous crop sensor bodies. Nothing like the dynamic range the K-1 sensor will give you.

I have not used a rear converter with my D-FA 150-450 and K-1 set up yet. From what other's have reported, IQ loss is minimal, so I'll have to pursue that extra reach sometime soon.

One thing I will say, using the K-1 with the D-FA 150-450 requires a different style of shooting that one normally would with a more "standard" lens. The setup is pretty heavy. I'd recommend using the Tav mode, shoot really fast (1/1000 minimum) and let your ISO go where it goes. The dynamic range is very very forgiving on the K-1, and I'm told even more forgiving on the K-1 Mark II.

07-09-2019, 05:33 AM - 1 Like	#6
derekkite Pentaxian Join Date: Sep 2011 Location: Nelson B.C. Posts: 3,782	Crop. Seriously crop. You will find the limits of the sensor density, your technique in keeping it sharp. To fill a 450mm screen with a squirrel means being really really close, and you get into another knarly problem of only it's nose being in focus. Nice shot by the way. Last edited by derekkite; 07-09-2019 at 06:50 AM.

07-09-2019, 05:51 PM	#12
catfishjohn Site Supporter Join Date: Oct 2016 Location: Arkansas Posts: 137	HD DA 1.4 x with DFA 150 to 450 I very often use the 1.4 with my 150-450. It gives more reach with little to no loss of IQ. There is an article on the forum which covers the pair in detail. Want even more? Just pair with a KP or K70. Using really long focal length comes with a whole new set of problems so there is a learning curve.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
HD PENTAX D FA 150 to 450mm ED DC AW Lens with K3 camera	Robert N	Pentax DSLR Discussion	4	11-13-2018 08:11 PM
Pentax HD PENTAX-D FA 150-450mm F4.5-5.6 ED DC AW Lens feedback	Robert N	Pentax SLR Lens Discussion	13	05-15-2018 12:40 PM
K3-II Performance With The Pentax HD PENTAX D FA 150-450mm f/4.5-5.6	mhsp1948	Pentax DSLR Discussion	15	03-20-2018 08:44 PM
PENTAX HD D FA DC AW 150-450mm F4.5-5.6 ZOOM LENS - BLACK Australia	Sorver	Pentax Price Watch	8	05-12-2015 01:49 AM

07-08-2019, 11:53 PM	#2
biz-engineer Pentaxian Join Date: Feb 2015 Photos: Gallery Posts: 12,232	Originally posted by crockpotveggies When I look at photos on the Flickr group, they're beautifully framed and subjects are filling the photo. Most are cropped. For subjects of 4 inches in size, to cover 1/3rd of the frame, the distance is 14 feet at 450mm. Sometimes in open spaces, I felt like being close enough, but when I measured the distance it was more than I initially thought (my experience).

07-09-2019, 12:06 AM	#3
crockpotveggies Junior Member Join Date: Jul 2019 Posts: 33 Original Poster	Originally posted by biz-engineer Most are cropped. For subjects of 4 inches in size, to cover 1/3rd of the frame, the distance is 14 feet at 450mm. Sometimes in open spaces, I felt like being close enough, but when I measured the distance it was more than I initially thought (my experience). Good to know, I guess I should have expected some cropping. So it sounds like it's time for me to work on my stealth, as I think a lot of these critters will be quite fearful of this barrel!

07-09-2019, 12:30 AM	#4
LensBeginner Veteran Member Join Date: Sep 2014 Photos: Albums Posts: 4,696	There's another factor - apart from crop factor and PP cropping - and that is the fact that focal length numbers are only true at infinity. Generally, the closer you get to your subject, the "shorter" the FL becomes, due to the way the zoom and focusing works. There were some threads about this WRT the 60-250, IIRC, where this phenomenon was quite apparent. A picture of an oven was involved. For instance: https://www.pentaxforums.com/forums/10-pentax-slr-lens-discussion/369979-foc...-its-said.html

07-09-2019, 01:44 AM	#5
biz-engineer Pentaxian Join Date: Feb 2015 Photos: Gallery Posts: 12,232	Originally posted by crockpotveggies o it sounds like it's time for me to work on my stealth, as I think a lot of these critters will be quite fearful of this barrel! Wildlife react mostly on movement (movement of the hand trying to reach the grip and shutter). If I know when the animal is going to be, I install my DFA150450 K1 kit on a gimbal and operate it from a distance, using the IR remote dongle or using my phone with Image Sync., allowing the camera to be closer to subject.

07-09-2019, 09:53 AM	#7
zapp Pentaxian Join Date: Jul 2011 Posts: 2,385	Focal length is 450 mm. Distance is 6000 mm. Magnificationfactor is thus 13. Frame is 24 mm in height, so you should fill the frame height with a 312 mm tall object. Squirrel covers 1/3 of the height, so it has 100 mm height or 4 inches. I don‘t think you have a problem. Maybe the distance was more like 30 feet... work on your technique and start cropping. 450 mm lens for small and shy objects is just the beginning.

07-09-2019, 12:08 PM	#8
Apet-Sure Site Supporter Join Date: Dec 2015 Location: Goldsboro North Carolina Photos: Gallery \| Albums Posts: 2,861	Originally posted by crockpotveggies And I'm not sure if it's just me or if it's because I've now gone full frame, but the subjects I'm capturing seem to be much farther away than I'd expect at 450mm. How long have you had your K-1? Did you use an APS-C sensor camera previously? You may already be aware of this, but 450mm on APS-C gives you the same field of view as 675mm on full frame. Conversely, 450mm on full frame gives you the same field of view as 300mm on APS-C. So, switching from a smaller sensor to a bigger sensor will make subjects seem farther away for any given focal length lens.

07-09-2019, 03:53 PM	#9
crockpotveggies Junior Member Join Date: Jul 2019 Posts: 33 Original Poster	Originally posted by Apet-Sure How long have you had your K-1? Did you use an APS-C sensor camera previously? You may already be aware of this, but 450mm on APS-C gives you the same field of view as 675mm on full frame. Conversely, 450mm on full frame gives you the same field of view as 300mm on APS-C. So, switching from a smaller sensor to a bigger sensor will make subjects seem farther away for any given focal length lens. It's only been a week on the K-1 so I'm still adjusting to full frame. Amazing, that's quite a difference between the sensor formats. Certainly explains why I'm experiencing this.

07-09-2019, 04:52 PM - 1 Like	#10
aslyfox Seeker of Knowledge Join Date: Aug 2016 Location: Topeka, Kansas Photos: Gallery \| Albums Posts: 24,581	Originally posted by Apet-Sure How long have you had your K-1? Did you use an APS-C sensor camera previously? You may already be aware of this, but 450mm on APS-C gives you the same field of view as 675mm on full frame. Conversely, 450mm on full frame gives you the same field of view as 300mm on APS-C. So, switching from a smaller sensor to a bigger sensor will make subjects seem farther away for any given focal length lens. this article and chart might help Crop Factor Explained

07-09-2019, 05:27 PM	#11
clickclick Loyal Site Supporter Join Date: May 2016 Location: East Coast Posts: 2,903	Originally posted by crockpotveggies It's only been a week on the K-1 so I'm still adjusting to full frame. Amazing, that's quite a difference between the sensor formats. Certainly explains why I'm experiencing this. What were you shooting with before the K-1?

07-09-2019, 06:11 PM - 1 Like	#13
aslyfox Seeker of Knowledge Join Date: Aug 2016 Location: Topeka, Kansas Photos: Gallery \| Albums Posts: 24,581	Testing the HD Pentax-DA 1.4x Teleconverter with the D FA 150-450mm on Full Frame Read more at: Testing the HD Pentax-DA 1.4x Teleconverter with the D FA 150-450mm on Full Frame Review - Introduction \| PentaxForums.com Reviews " The Bottom Line Using the HD Pentax-DA 1.4x AW AF with the HD D FA 150-450mm yields an impressive effective maximum focal length. Optical performance remains comparable to that of the lens alone. The pair cannot be used in full frame mode but, apart from that, there is nothing to stop users from pairing the two. " Read more at: https://www.pentaxforums.com/reviews/da-14x-teleconverter-150-450mm-fullfram...#ixzz5tEVDUw5u

07-09-2019, 07:44 PM	#14
crockpotveggies Junior Member Join Date: Jul 2019 Posts: 33 Original Poster	Thanks for that review! I actually just ordered the new 1.4x rear converter. It shows up tomorrow I'm quite excited to test it out. Should be great for birding.

07-09-2019, 11:12 PM	#15
david94903 Loyal Site Supporter Join Date: Nov 2010 Location: San Rafael, CA Photos: Gallery \| Albums Posts: 806	I shoot a lot with the D-FA 150-450 on my K-1, and I crop my images a lot to get the final image I want. You can see many of my "cropped" images on my Flickr page. I'm rarely 20' away from my subject, usually more like 50' to 100' on average, and often further. And you'll quickly discover that the K-1 will offer excellent cropping opportunities that weren't even possible with any of your previous crop sensor bodies. Nothing like the dynamic range the K-1 sensor will give you. I have not used a rear converter with my D-FA 150-450 and K-1 set up yet. From what other's have reported, IQ loss is minimal, so I'll have to pursue that extra reach sometime soon. One thing I will say, using the K-1 with the D-FA 150-450 requires a different style of shooting that one normally would with a more "standard" lens. The setup is pretty heavy. I'd recommend using the Tav mode, shoot really fast (1/1000 minimum) and let your ISO go where it goes. The dynamic range is very very forgiving on the K-1, and I'm told even more forgiving on the K-1 Mark II.