K1 and F 35-70 3.5-4.5

PiotrKrochmal · 11-07-2016, 02:25 PM - **2 Likes**

Hi,
I wanted to have something small and usefull and ofc cheap for my K1. Not always need to take 24-70. I read whole internet (almost hehe).
And I've focused on old Pentax F 35-70 f/3.5-4.5.
From 3 different copies I bought the priciest = 56$

almost mint condition.
What is curious. There is no similar lens for smaller sensors. Similar = almost equivalent. Why?
FF 35-70 f/3.5-4.5. = APSC 23-46 f/2-3,5 = m4/3 17-35 f/1.5-2.5
So in term of crop sensor it is still bright lens

.
One great thing: in Macro mode AF is still functional.
Question: is macro usable? ask Lamas
So what I've learned today? Limited 20-40 is nothing new in Pentax world. But it will be nice to see new version of 35-70 updated but still as small as original but with new technology.
All photos with exif.
more and bigger versions in dedicated smugmug gallery: F 35-70 3.5-4.5 - krochmal

Adam · 11-07-2016, 04:22 PM

Originally posted by PiotrKrochmal

FF 35-70 f/3.5-4.5. = APSC 23-46 f/2-3,5 = m4/3 17-35 f/1.5-2.5

You got the focal lengths right, but it would be f/3.5-4.5 for all 3. Looks like crop users get something very similar in the DA 20-40mm F2.8-4

Very nice photos!

chti · 11-07-2016, 04:40 PM

I´m also looking for a lightweight F 35-70 or F 35-105 for my K1. Your pictures look very promising, I´ve to intensify my search

banep · 11-08-2016, 01:44 AM

Originally posted by chti

I´m also looking for a lightweight F 35-70 or F 35-105 for my K1. Your pictures look very promising, I´ve to intensify my search

F35-70 is a great little lens and it is better than F35-105.
Lens is a little soft at 35mm wide open, but @f/4.5 a good copy is very sharp through entire zoom range on K1.

Last edited by banep; 11-08-2016 at 03:33 AM.

PiotrKrochmal · 11-08-2016, 03:08 AM

Originally posted by Adam

You got the focal lengths right, but it would be f/3.5-4.5 for all 3. Looks like crop users get something very similar in the DA 20-40mm F2.8-4

Very nice photos!

My aperture calculation was made to show what lens you need to have similar DOF and bokeh

**clackers** · 11-08-2016, 03:52 AM

Originally posted by PiotrKrochmal

My aperture calculation was made to show what lens you need to have similar DOF and bokeh

That's misleading, Piotr.

Aperture ratings don't change on a lens because of the sensor behind it.

I do have that 35-70, BTW, and like what it does for the size.

You might consider pairing it with the FA J 18-35, FA 20-35 or DA 16-45.

PiotrKrochmal · 11-08-2016, 04:15 AM

Originally posted by clackers

That's misleading, Piotr.

Aperture ratings don't change on a lens because of the sensor behind it.

I do have that 35-70, BTW, and like what it does for the size.

You might consider pairing it with the FA J 18-35, FA 20-35 or DA 16-45.

I' have to humble disagree. As far as I know it aperture equivalent work this way.
There is good article What is equivalence and why should I care?: Digital Photography Review

**clackers** · 11-08-2016, 04:53 AM

Originally posted by PiotrKrochmal

I' have to humble disagree. As far as I know it aperture equivalent work this way.
There is good article What is equivalence and why should I care?: Digital Photography Review

I've read it, Piotr, it was terrible back then, it's terrible now.

Please don't be quoting Richard Butler at us!

PiotrKrochmal · 11-08-2016, 06:06 AM

Originally posted by clackers

I've read it, Piotr, it was terrible back then, it's terrible now.

Please don't be quoting Richard Butler at us!

why? Hey he wrote that quite nicely.
And as you suggest I'm hunting now 20-35. But without rush as I have fish F 17-28 for super wide angle shots. DFA 15-30 is simply over priced and too big for me.

chti · 11-08-2016, 02:56 PM

Originally posted by banep

F35-70 is a great little lens and it is better than F35-105.
Lens is a little soft at 35mm wide open, but @f/4.5 a good copy is very sharp through entire zoom range on K1.

This sounds good. I will be patient and wait for a good offer. They pop up from time to time here in Germany for small money.

Quote:

And as you suggest I'm hunting now 20-35.

Go for it! It´s an excellent little lens. A bit plasticy, but optics are very good.

**clackers** · 11-08-2016, 04:26 PM

Originally posted by PiotrKrochmal

why? Hey he wrote that quite nicely.

That Equivalence stuff falls into the category (depending on who wrote it) of trivial, misleading, or BS.

You can use a crop factor very quickly to determine the field of view of a lens, but extending to aperture or anything else starts to get laughable. The discussions end up as controversial as gun control or abortion, so I'll simply point to this other article for you to read. I don't agree with all it contains, but at least it's only two pages.

"Full Frame Equivalence" and Why It Doesn't Matter - Admiring Light

Originally posted by PiotrKrochmal

And as you suggest I'm hunting now 20-35. But without rush as I have fish F 17-28 for super wide angle shots. DFA 15-30 is simply over priced and too big for me.

You will have to balance this, PK. I have the 20-35, but would get the 15-30 if I could afford it.

It's one of the best UWA lens ever made, beating the mighty Nikon 14-24 according to various reviewers.

**felixkh** · 11-08-2016, 05:34 PM

You might want to look at the Irix 15mm F2.4 Firefly IF you are into landscapes.

normhead · 11-08-2016, 06:13 PM - **1 Like**

Originally posted by PiotrKrochmal

I' have to humble disagree. As far as I know it aperture equivalent work this way.
There is good article What is equivalence and why should I care?: Digital Photography Review

Can you answer this question.

I determine that the exposure on my APS_c camera is 100 ISO, ƒ.5.6, 1/100s

What is the correct exposure on a 36x24 sensor (pick the best answer)

1. 100 ISO, ƒ.5.6, 1/100s
2. 100 ISO, ƒ.8, 1/100s
3. 200 ISO, ƒ.5.6, 1/100s

If you're so messed up you can't accurately answer the question, i's because you don't know as much about exposure as one of my photography students would have known after a week. Anyone who has used the same hand held light meter for exposures on different formats will know the answer immediately.

Exposure is not affect by format. What is good on one is good on them all. However when looking at your light meter, it' like a little hand held computer that gives you all the different exposures you could use. And you will select one of them based on the desired depth of field for that format. The exposure value however is unaffected.

surfar · 11-09-2016, 01:56 AM - **1 Like**

The F35-70mm, is a great little lens(well my 2 are)...highly recommend it....Plenty of other F series and FA series produce very good images on the K1.

It has an affinity with 1...because the images from the K-01 are also impressive.

**Rondec** · 11-09-2016, 03:38 AM - **1 Like**

Originally posted by normhead

Can you answer this question.

I determine that the exposure on my APS_c camera is 100 ISO, ƒ.5.6, 1/100s

What is the correct exposure on a 36x24 sensor (pick the best answer)

1. 100 ISO, ƒ.5.6, 1/100s
2. 100 ISO, ƒ.8, 1/100s
3. 200 ISO, ƒ.5.6, 1/100s

If you're so messed up you can't accurately answer the question, i's because you don't know as much about exposure as one of my photography students would have known after a week. Anyone who has used the same hand held light meter for exposures on different formats will know the answer immediately.

Exposure is not affect by format. What is good on one is good on them all. However when looking at your light meter, it' like a little hand held computer that gives you all the different exposures you could use. And you will select one of them based on the desired depth of field for that format. The exposure value however is unaffected.

The answer is probably (1), although I would probably choose iso 200, f8, and 1/100s.

11-07-2016, 02:25 PM - 2 Likes	#1
PiotrKrochmal Senior Member Join Date: May 2010 Location: Poland -> Kraków Posts: 199	K1 and F 35-70 3.5-4.5 Hi, I wanted to have something small and usefull and ofc cheap for my K1. Not always need to take 24-70. I read whole internet (almost hehe). And I've focused on old Pentax F 35-70 f/3.5-4.5. From 3 different copies I bought the priciest = 56$ almost mint condition. What is curious. There is no similar lens for smaller sensors. Similar = almost equivalent. Why? FF 35-70 f/3.5-4.5. = APSC 23-46 f/2-3,5 = m4/3 17-35 f/1.5-2.5 So in term of crop sensor it is still bright lens . One great thing: in Macro mode AF is still functional. Question: is macro usable? ask Lamas So what I've learned today? Limited 20-40 is nothing new in Pentax world. But it will be nice to see new version of 35-70 updated but still as small as original but with new technology. All photos with exif. more and bigger versions in dedicated smugmug gallery: F 35-70 3.5-4.5 - krochmal

11-07-2016, 04:22 PM	#2
Adam Administrator Site Webmaster Join Date: Sep 2006 Location: Arizona Photos: Gallery \| Albums Posts: 51,595	Originally posted by PiotrKrochmal FF 35-70 f/3.5-4.5. = APSC 23-46 f/2-3,5 = m4/3 17-35 f/1.5-2.5 You got the focal lengths right, but it would be f/3.5-4.5 for all 3. Looks like crop users get something very similar in the DA 20-40mm F2.8-4 Very nice photos! Adam PentaxForums.com Webmaster (Site Usage Guide \| Site Help \| My Photography) PentaxForums.com server and development costs are user-supported. You can help cover these costs by donating or purchasing one of our Pentax eBooks. Or, buy your photo gear from our affiliates, Adorama, B&H Photo, KEH, or Topaz Labs, and get FREE Marketplace access - click here to see how! Trusted Pentax retailers:

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
SMC A 35-70 f/3.5-4.5 Macro	Jean Poitiers	Lens Sample Photo Archive	5	10-02-2019 12:36 PM
For Sale - Sold: Pentax F 35-70/3.5-4.5 macro and K-01	chiepapi	Sold Items	11	12-22-2015 09:44 PM
For Sale - Sold: SMC Pentax-F Zoom 1:3.5-4.5 35-70 mm	Arjay Bee	Sold Items	8	11-01-2015 05:19 PM
For Sale - Sold: Pentax F 70-210mm 4-5.6 and Pentax F 35-70mm 3.5-4.5 Macro and SF1 camera Body	jjdgti	Sold Items	5	12-30-2009 12:25 PM
For Sale - Sold: Pentax 300mm f/4.0, Tokina AF 19-35 f/3.5-4.5, Vivitar Series 1 70-210mm f/3.5	hinman	Sold Items	9	11-14-2008 04:52 PM

11-07-2016, 04:40 PM	#3
chti Forum Member Join Date: Nov 2013 Location: Berlin Posts: 62	I´m also looking for a lightweight F 35-70 or F 35-105 for my K1. Your pictures look very promising, I´ve to intensify my search

11-08-2016, 01:44 AM	#4
banep Banned Join Date: Mar 2013 Posts: 360	Originally posted by chti I´m also looking for a lightweight F 35-70 or F 35-105 for my K1. Your pictures look very promising, I´ve to intensify my search F35-70 is a great little lens and it is better than F35-105. Lens is a little soft at 35mm wide open, but @f/4.5 a good copy is very sharp through entire zoom range on K1. Last edited by banep; 11-08-2016 at 03:33 AM.

11-08-2016, 03:08 AM	#5
PiotrKrochmal Senior Member Join Date: May 2010 Location: Poland -> Kraków Posts: 199 Original Poster	Originally posted by Adam You got the focal lengths right, but it would be f/3.5-4.5 for all 3. Looks like crop users get something very similar in the DA 20-40mm F2.8-4 Very nice photos! My aperture calculation was made to show what lens you need to have similar DOF and bokeh

11-08-2016, 03:52 AM	#6
clackers Otis Memorial Pentaxian Join Date: Jul 2013 Location: Melbourne Photos: Albums Posts: 16,397	Originally posted by PiotrKrochmal My aperture calculation was made to show what lens you need to have similar DOF and bokeh That's misleading, Piotr. Aperture ratings don't change on a lens because of the sensor behind it. I do have that 35-70, BTW, and like what it does for the size. You might consider pairing it with the FA J 18-35, FA 20-35 or DA 16-45.

11-08-2016, 04:15 AM	#7
PiotrKrochmal Senior Member Join Date: May 2010 Location: Poland -> Kraków Posts: 199 Original Poster	Originally posted by clackers That's misleading, Piotr. Aperture ratings don't change on a lens because of the sensor behind it. I do have that 35-70, BTW, and like what it does for the size. You might consider pairing it with the FA J 18-35, FA 20-35 or DA 16-45. I' have to humble disagree. As far as I know it aperture equivalent work this way. There is good article What is equivalence and why should I care?: Digital Photography Review

11-08-2016, 04:53 AM	#8
clackers Otis Memorial Pentaxian Join Date: Jul 2013 Location: Melbourne Photos: Albums Posts: 16,397	Originally posted by PiotrKrochmal I' have to humble disagree. As far as I know it aperture equivalent work this way. There is good article What is equivalence and why should I care?: Digital Photography Review I've read it, Piotr, it was terrible back then, it's terrible now. Please don't be quoting Richard Butler at us!

11-08-2016, 06:06 AM	#9
PiotrKrochmal Senior Member Join Date: May 2010 Location: Poland -> Kraków Posts: 199 Original Poster	Originally posted by clackers I've read it, Piotr, it was terrible back then, it's terrible now. Please don't be quoting Richard Butler at us! why? Hey he wrote that quite nicely. And as you suggest I'm hunting now 20-35. But without rush as I have fish F 17-28 for super wide angle shots. DFA 15-30 is simply over priced and too big for me.

11-08-2016, 02:56 PM	#10
chti Forum Member Join Date: Nov 2013 Location: Berlin Posts: 62	Originally posted by banep F35-70 is a great little lens and it is better than F35-105. Lens is a little soft at 35mm wide open, but @f/4.5 a good copy is very sharp through entire zoom range on K1. This sounds good. I will be patient and wait for a good offer. They pop up from time to time here in Germany for small money. Quote: And as you suggest I'm hunting now 20-35. Go for it! It´s an excellent little lens. A bit plasticy, but optics are very good.

11-08-2016, 04:26 PM	#11
clackers Otis Memorial Pentaxian Join Date: Jul 2013 Location: Melbourne Photos: Albums Posts: 16,397	Originally posted by PiotrKrochmal why? Hey he wrote that quite nicely. That Equivalence stuff falls into the category (depending on who wrote it) of trivial, misleading, or BS. You can use a crop factor very quickly to determine the field of view of a lens, but extending to aperture or anything else starts to get laughable. The discussions end up as controversial as gun control or abortion, so I'll simply point to this other article for you to read. I don't agree with all it contains, but at least it's only two pages. "Full Frame Equivalence" and Why It Doesn't Matter - Admiring Light Originally posted by PiotrKrochmal And as you suggest I'm hunting now 20-35. But without rush as I have fish F 17-28 for super wide angle shots. DFA 15-30 is simply over priced and too big for me. You will have to balance this, PK. I have the 20-35, but would get the 15-30 if I could afford it. It's one of the best UWA lens ever made, beating the mighty Nikon 14-24 according to various reviewers.

11-08-2016, 05:34 PM	#12
felixkh Site Supporter Join Date: Nov 2008 Location: Singapore Photos: Gallery Posts: 1,201	You might want to look at the Irix 15mm F2.4 Firefly IF you are into landscapes.

11-08-2016, 06:13 PM - 1 Like	#13
normhead Pentaxian Join Date: Jun 2007 Location: Near Algonquin Park Photos: Gallery \| Albums Posts: 40,451	Originally posted by PiotrKrochmal I' have to humble disagree. As far as I know it aperture equivalent work this way. There is good article What is equivalence and why should I care?: Digital Photography Review Can you answer this question. I determine that the exposure on my APS_c camera is 100 ISO, ƒ.5.6, 1/100s What is the correct exposure on a 36x24 sensor (pick the best answer) 1. 100 ISO, ƒ.5.6, 1/100s 2. 100 ISO, ƒ.8, 1/100s 3. 200 ISO, ƒ.5.6, 1/100s If you're so messed up you can't accurately answer the question, i's because you don't know as much about exposure as one of my photography students would have known after a week. Anyone who has used the same hand held light meter for exposures on different formats will know the answer immediately. Exposure is not affect by format. What is good on one is good on them all. However when looking at your light meter, it' like a little hand held computer that gives you all the different exposures you could use. And you will select one of them based on the desired depth of field for that format. The exposure value however is unaffected.

11-09-2016, 01:56 AM - 1 Like	#14
surfar Pentaxian Join Date: Jan 2015 Location: mid nth coast,nsw Photos: Gallery Posts: 6,141	The F35-70mm, is a great little lens(well my 2 are)...highly recommend it....Plenty of other F series and FA series produce very good images on the K1. It has an affinity with 1...because the images from the K-01 are also impressive.

11-09-2016, 03:38 AM - 1 Like	#15
Rondec Loyal Site Supporter Join Date: Mar 2009 Location: Gladys, Virginia Photos: Gallery Posts: 27,653	Originally posted by normhead Can you answer this question. I determine that the exposure on my APS_c camera is 100 ISO, ƒ.5.6, 1/100s What is the correct exposure on a 36x24 sensor (pick the best answer) 1. 100 ISO, ƒ.5.6, 1/100s 2. 100 ISO, ƒ.8, 1/100s 3. 200 ISO, ƒ.5.6, 1/100s If you're so messed up you can't accurately answer the question, i's because you don't know as much about exposure as one of my photography students would have known after a week. Anyone who has used the same hand held light meter for exposures on different formats will know the answer immediately. Exposure is not affect by format. What is good on one is good on them all. However when looking at your light meter, it' like a little hand held computer that gives you all the different exposures you could use. And you will select one of them based on the desired depth of field for that format. The exposure value however is unaffected. The answer is probably (1), although I would probably choose iso 200, f8, and 1/100s.