HD 20-40 Ltd Starburst

superdave · 12-20-2016, 06:32 AM

Originally posted by slartibartfast01

ht moon looks like the sun to me .

haha you probably right

but the dark foreground made me think about blue hour

Originally posted by chrisfer

Pentax K-5 II & HD 20-40mm @ 20 mm f/8 4s 80 ISO

Not very well defined, Unfortunately a little slobbery...

Same bridge, same hour, with the 15mm :
Pentax K-5 II & SMC 15mm @ f/6,7 30s 80 ISO

Thanks, that's a perfect example! I think I'd better to forget the 20-40mm if I look for well definied defined starbursts... and go for the 40mm smc as my next lens to purchase.

---------- Post added 12-20-2016 at 02:43 PM ----------

Originally posted by bdery

Here's an example of the SMC DA40:

It doesn't compare at all with what you'd get with a SMC DA15 or DA21. Closing down the aperture could help, but it's not a fair comparison. The closest you'll get is probably the FA31 which has 9 straight blades. Even if it cannot compare to the two best, it's better than most.

Thanks for the photo. No starburst at all, but I don't expect any starburst at 1 sec @ f/2.8. I am however impressed by the 21mm in your gallery, with nearly the same settings

p.s. ton site à l'air sympa, je vais aller voir ça

EDIT : bdery, I came across this photo taken with the da 40mm on your website (https://bernard-dery.smugmug.com/Nature/Nature-et-ville/i-7CV8szF) and with 5 sec @ f/6.3, I am disapointed to not see any starburst

May be it is because the light is to close to the camera.

Last edited by superdave; 12-20-2016 at 07:06 AM. Reason: Add detaills

**grahame** · 12-20-2016, 07:57 AM

Originally posted by kh1234567890

My DA16-45 does starbursts even wide open, defying the laws of physics, apparently ...

DA16-45 has F4 in the entire range. It could be F 3.2 at 16mm. Pentax limited the aperture at F4 at wide end. If you look through the lens while keeping the aperture open, you will see the aperture is partially closed. That is why you can see starburst "wide-open" at 16mm. try again at 45mm, you won't see it.
laws of physics still applies.

bdery · 12-20-2016, 09:44 AM

Originally posted by superdave

Thanks for the photo. No starburst at all, but I don't expect any starburst at 1 sec @ f/2.8. I am however impressed by the 21mm in your gallery, with nearly the same settings

That was my point, the 21 (and 15 which I don't own) deliver consistently, while most lenses, including the 40, struggle.

Originally posted by superdave

p.s. ton site à l'air sympa, je vais aller voir ça

Merci!

Originally posted by superdave

EDIT : bdery, I came across this photo taken with the da 40mm on your website (Nature et ville - bernard-dery) and with 5 sec @ f/6.3, I am disapointed to not see any starburst May be it is because the light is to close to the camera.

It's hard to generate starbursts with the 40, whatever the conditions.

I've been looking for a full frame equivalent to the 21 recently. I've looked at samples from the F28, FA*24, FA31, I've tested the FA28 for a while. Nothing comes close, sadly. That lens, and the 15, are pretty unique (and it needs to be the SMC version, Pentax sadly crippled them with the circular aperture on the HD version).

I think the best bet is to use the 21 on a high-res sensor, and crop as needed.

**lithedreamer** · 12-20-2016, 10:41 AM

Maybe it's too telephoto given the APS-C crop factor, maybe not, but the FA 43 Limited can starburst:

kh1234567890 · 12-20-2016, 12:04 PM

Originally posted by grahame

DA16-45 has F4 in the entire range. It could be F 3.2 at 16mm. Pentax limited the aperture at F4 at wide end. If you look through the lens while keeping the aperture open, you will see the aperture is partially closed. That is why you can see starburst "wide-open" at 16mm. try again at 45mm, you won't see it.
laws of physics still applies.

So it does. I'd never noticed that.

**pepperberry farm** · 12-20-2016, 05:53 PM - **1 Like**

I've been getting nice starbursts from my Tamron 17mm lens:

but I'll be the first to admit - this is not a replacement for a DA15...

superdave · 12-21-2016, 01:43 AM

Originally posted by pepperberry farm

I've been getting nice starbursts from my Tamron 17mm lens:

but I'll be the first to admit - this is not a replacement for a DA15...

Didn't know that lens but starbursts are really nice !

However I already own the 12-24 which produce the same 8-stroke starbursts than your lens, so I need something between 24 and 70.
Morevove I really like the rendering of my 70mm limited lens so I would like to continue with the limited serie; and I don't want to buy tamron/sigma anymore as they stopped to make pentax lens.

**pepperberry farm** · 12-21-2016, 01:56 AM

Originally posted by superdave

and I don't want to buy tamron/sigma anymore as they stopped to make pentax lens.

they did?

superdave · 12-21-2016, 05:53 AM

Originally posted by pepperberry farm

they did?

Yes... all new lenses are Canon and Nikon only... Sony sometime but no more Pentax sadly.

**pepperberry farm** · 12-21-2016, 06:03 AM

OK - a quick perusal of B&H or Adorama shows both SIgma and Tamron lenses in Pentax K-mount, so I'm not sure why you're stating that neither are making Pentax lenses anymore...

granted, they are not making as many as they used to, but there are still both brands available in K-mount....

Blacknight659 · 12-21-2016, 08:38 AM - **2 Likes**

As others here are showing, the 20-40 limited is a technically near perfect lens. I believe the starbursts achieved in other lenses like the 15mm limited represents an exploitation of a lens design. I doubt the creators were going for this, and "corrected" it with the new 15mm HD by adding rounded blades. Similar lenses are popular for their "flaws" like the Helios 44-2 with the swirl effect.

The 20-40 lens is wonderful, but I think if you are into starbursts, you may want to look for another lens and specifically one that has non rounded blades.

superdave · 12-21-2016, 08:55 AM

Originally posted by pepperberry farm

OK - a quick perusal of B&H or Adorama shows both SIgma and Tamron lenses in Pentax K-mount, so I'm not sure why you're stating that neither are making Pentax lenses anymore...

granted, they are not making as many as they used to, but there are still both brands available in K-mount....

Just because the lasted Sigma lenses released are not K-Mount (i.e. 50-100mm, 85mm, 500mm, 12-24mm, 150-600mm, 24-35mm, etc..) and I can't remember what is the latest Tamron lens in K-Mount... nothing new for a while.

Of course you can still purchase their old models... but I don't expect they release something new for K-Mount in a near future.

**clackers** · 12-21-2016, 09:06 AM

Originally posted by pepperberry farm

OK - a quick perusal of B&H or Adorama shows both SIgma and Tamron lenses in Pentax K-mount, so I'm not sure why you're stating that neither are making Pentax lenses anymore...

They're all old lenses, Pepperberry Farm, and they've discontinued many models.

For the last two years the releases have been Canikon ... it doesn't look promising for K-mount.

**pepperberry farm** · 12-21-2016, 09:25 AM

gotcha - not releasing their newest models in K-mount is the issue; not that they aren't actually manufacturing anything for Pentax, just not the latest and greatest...

thanks for the clarification....

**clackers** · 12-21-2016, 09:39 AM

Originally posted by pepperberry farm

gotcha - not releasing their newest models in K-mount is the issue; not that they aren't actually manufacturing anything for Pentax, just not the latest and greatest...

thanks for the clarification....

They may also only be drawing down on inventory, PF, and not making any new ones.

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12-20-2016, 06:32 AM	#31
superdave Senior Member Join Date: Apr 2009 Posts: 228	Originally posted by slartibartfast01 ht moon looks like the sun to me . haha you probably right but the dark foreground made me think about blue hour Originally posted by chrisfer Pentax K-5 II & HD 20-40mm @ 20 mm f/8 4s 80 ISO Not very well defined, Unfortunately a little slobbery... Same bridge, same hour, with the 15mm : Pentax K-5 II & SMC 15mm @ f/6,7 30s 80 ISO Thanks, that's a perfect example! I think I'd better to forget the 20-40mm if I look for well definied defined starbursts... and go for the 40mm smc as my next lens to purchase. ---------- Post added 12-20-2016 at 02:43 PM ---------- Originally posted by bdery Here's an example of the SMC DA40: It doesn't compare at all with what you'd get with a SMC DA15 or DA21. Closing down the aperture could help, but it's not a fair comparison. The closest you'll get is probably the FA31 which has 9 straight blades. Even if it cannot compare to the two best, it's better than most. Thanks for the photo. No starburst at all, but I don't expect any starburst at 1 sec @ f/2.8. I am however impressed by the 21mm in your gallery, with nearly the same settings p.s. ton site à l'air sympa, je vais aller voir ça EDIT : bdery, I came across this photo taken with the da 40mm on your website (https://bernard-dery.smugmug.com/Nature/Nature-et-ville/i-7CV8szF) and with 5 sec @ f/6.3, I am disapointed to not see any starburst May be it is because the light is to close to the camera. Last edited by superdave; 12-20-2016 at 07:06 AM. Reason: Add detaills

12-20-2016, 07:57 AM	#32
grahame Loyal Site Supporter Join Date: Aug 2011 Photos: Albums Posts: 2,041	Originally posted by kh1234567890 My DA16-45 does starbursts even wide open, defying the laws of physics, apparently ... DA16-45 has F4 in the entire range. It could be F 3.2 at 16mm. Pentax limited the aperture at F4 at wide end. If you look through the lens while keeping the aperture open, you will see the aperture is partially closed. That is why you can see starburst "wide-open" at 16mm. try again at 45mm, you won't see it. laws of physics still applies.

12-20-2016, 09:44 AM	#33
bdery Pentaxian Join Date: Mar 2008 Location: Quebec city, Canada Photos: Gallery Posts: 9,357	Originally posted by superdave Thanks for the photo. No starburst at all, but I don't expect any starburst at 1 sec @ f/2.8. I am however impressed by the 21mm in your gallery, with nearly the same settings That was my point, the 21 (and 15 which I don't own) deliver consistently, while most lenses, including the 40, struggle. Originally posted by superdave p.s. ton site à l'air sympa, je vais aller voir ça Merci! Originally posted by superdave EDIT : bdery, I came across this photo taken with the da 40mm on your website (Nature et ville - bernard-dery) and with 5 sec @ f/6.3, I am disapointed to not see any starburst May be it is because the light is to close to the camera. It's hard to generate starbursts with the 40, whatever the conditions. I've been looking for a full frame equivalent to the 21 recently. I've looked at samples from the F28, FA*24, FA31, I've tested the FA28 for a while. Nothing comes close, sadly. That lens, and the 15, are pretty unique (and it needs to be the SMC version, Pentax sadly crippled them with the circular aperture on the HD version). I think the best bet is to use the 21 on a high-res sensor, and crop as needed.

12-20-2016, 10:41 AM	#34
lithedreamer Site Supporter Join Date: Sep 2013 Photos: Gallery \| Albums Posts: 1,799	Maybe it's too telephoto given the APS-C crop factor, maybe not, but the FA 43 Limited can starburst:

12-20-2016, 12:04 PM	#35
kh1234567890 Veteran Member Join Date: Sep 2010 Location: Manchester, UK Photos: Gallery Posts: 2,653	Originally posted by grahame DA16-45 has F4 in the entire range. It could be F 3.2 at 16mm. Pentax limited the aperture at F4 at wide end. If you look through the lens while keeping the aperture open, you will see the aperture is partially closed. That is why you can see starburst "wide-open" at 16mm. try again at 45mm, you won't see it. laws of physics still applies. So it does. I'd never noticed that.

12-20-2016, 05:53 PM - 1 Like	#36
pepperberry farm amateur dirt farmer Join Date: Dec 2014 Location: probably out in a field somewhere... Photos: Gallery \| Albums Posts: 41,676	I've been getting nice starbursts from my Tamron 17mm lens: but I'll be the first to admit - this is not a replacement for a DA15...

12-21-2016, 01:43 AM	#37
superdave Senior Member Join Date: Apr 2009 Posts: 228	Originally posted by pepperberry farm I've been getting nice starbursts from my Tamron 17mm lens: but I'll be the first to admit - this is not a replacement for a DA15... Didn't know that lens but starbursts are really nice ! However I already own the 12-24 which produce the same 8-stroke starbursts than your lens, so I need something between 24 and 70. Morevove I really like the rendering of my 70mm limited lens so I would like to continue with the limited serie; and I don't want to buy tamron/sigma anymore as they stopped to make pentax lens.

12-21-2016, 01:56 AM	#38
pepperberry farm amateur dirt farmer Join Date: Dec 2014 Location: probably out in a field somewhere... Photos: Gallery \| Albums Posts: 41,676	Originally posted by superdave and I don't want to buy tamron/sigma anymore as they stopped to make pentax lens. they did?

12-21-2016, 05:53 AM	#39
superdave Senior Member Join Date: Apr 2009 Posts: 228	Originally posted by pepperberry farm they did? Yes... all new lenses are Canon and Nikon only... Sony sometime but no more Pentax sadly.

12-21-2016, 06:03 AM	#40
pepperberry farm amateur dirt farmer Join Date: Dec 2014 Location: probably out in a field somewhere... Photos: Gallery \| Albums Posts: 41,676	OK - a quick perusal of B&H or Adorama shows both SIgma and Tamron lenses in Pentax K-mount, so I'm not sure why you're stating that neither are making Pentax lenses anymore... granted, they are not making as many as they used to, but there are still both brands available in K-mount....

12-21-2016, 08:38 AM - 2 Likes	#41
Blacknight659 Veteran Member Join Date: Aug 2013 Photos: Gallery \| Albums Posts: 731	As others here are showing, the 20-40 limited is a technically near perfect lens. I believe the starbursts achieved in other lenses like the 15mm limited represents an exploitation of a lens design. I doubt the creators were going for this, and "corrected" it with the new 15mm HD by adding rounded blades. Similar lenses are popular for their "flaws" like the Helios 44-2 with the swirl effect. The 20-40 lens is wonderful, but I think if you are into starbursts, you may want to look for another lens and specifically one that has non rounded blades.

12-21-2016, 08:55 AM	#42
superdave Senior Member Join Date: Apr 2009 Posts: 228	Originally posted by pepperberry farm OK - a quick perusal of B&H or Adorama shows both SIgma and Tamron lenses in Pentax K-mount, so I'm not sure why you're stating that neither are making Pentax lenses anymore... granted, they are not making as many as they used to, but there are still both brands available in K-mount.... Just because the lasted Sigma lenses released are not K-Mount (i.e. 50-100mm, 85mm, 500mm, 12-24mm, 150-600mm, 24-35mm, etc..) and I can't remember what is the latest Tamron lens in K-Mount... nothing new for a while. Of course you can still purchase their old models... but I don't expect they release something new for K-Mount in a near future.

12-21-2016, 09:06 AM	#43
clackers Otis Memorial Pentaxian Join Date: Jul 2013 Location: Melbourne Photos: Albums Posts: 16,397	Originally posted by pepperberry farm OK - a quick perusal of B&H or Adorama shows both SIgma and Tamron lenses in Pentax K-mount, so I'm not sure why you're stating that neither are making Pentax lenses anymore... They're all old lenses, Pepperberry Farm, and they've discontinued many models. For the last two years the releases have been Canikon ... it doesn't look promising for K-mount.

12-21-2016, 09:25 AM	#44
pepperberry farm amateur dirt farmer Join Date: Dec 2014 Location: probably out in a field somewhere... Photos: Gallery \| Albums Posts: 41,676	gotcha - not releasing their newest models in K-mount is the issue; not that they aren't actually manufacturing anything for Pentax, just not the latest and greatest... thanks for the clarification....

12-21-2016, 09:39 AM	#45
clackers Otis Memorial Pentaxian Join Date: Jul 2013 Location: Melbourne Photos: Albums Posts: 16,397	Originally posted by pepperberry farm gotcha - not releasing their newest models in K-mount is the issue; not that they aren't actually manufacturing anything for Pentax, just not the latest and greatest... thanks for the clarification.... They may also only be drawing down on inventory, PF, and not making any new ones.