FAQ FAQ  Forum Search   Events   Register Register  Login Login

Minolta 28-70 f/2.8 G hood issues

Page  123 9>
Author
MichelvA View Drop Down
Alpha Eyes group
Alpha Eyes group
Knowledge Base Contributor

Joined: 26 April 2008
Country: Netherlands
Status: Offline
Posts: 17579
Post Options Post Options   Quote MichelvA Quote  Post ReplyReply Direct Link To This Post Topic: Minolta 28-70 f/2.8 G hood issues
    Posted: 27 December 2008 at 23:32
As some will remember, the hood of this lens was discussed here some time ago. I have tried several hoods, just to get it fitted, so i could find out whether the standard hood is too small.
So far i have bought the 20/2.8 hood, which has a petal shape, but is hardly big enough for the G. It even looks silly. I am going to use it as a base for a bigger hood. Also, the 85/1.4 hood fits, but looks silly/too small too.
Today i was mainly shooting with the new 70-200 SSM, but also did some shots with the 28-70 G. The past months i had found that the 28-70 gives less contrast under certain conditions . Usually with sun coming from the side (see also my own review).
Suddenly i remembered someone wrote in his review he used his hand to shield the lens from incoming sunlight. So i tried if this made a difference. See the following pictures. Don't mind the photograpic "quality" of the photo, it was especially made to show the effect.

#1 Subject is two small animals in front of the lens (doh), sun coming from left. This day was a typical sunny winter day, temperature -1 - +1 degrees Celcius.
Standard lens hood used. Watch the contrast, or lack of it. I used to change some parameters in the RAW files. This can give nice results. Not always.


#2 Same situation, now i held my hand to the left of the hood so it covered approximatly half of my hand. This almost gives the effect of a 40-50 mm deep hood.


I will follow up the fabrication of the new hood, unless someone can convince me i am doing something wrong here. Any comments welcome.

edit: forgot to mention: no editing of any form done, only resizing.



Edited by MichelvA - 27 December 2008 at 23:34
 



Back to Top
Maffe View Drop Down
Moderator Group
Moderator Group

Joined: 11 November 2005
Country: Sweden
Location: Sweden
Status: Offline
Posts: 11786
Post Options Post Options   Quote Maffe Quote  Post ReplyReply Direct Link To This Post Posted: 05 January 2009 at 07:44
I always used the 85/1.4 hood on my 28-70G, worked perfect.
The Standard hood is simple ridiculous!
Back to Top
MichelvA View Drop Down
Alpha Eyes group
Alpha Eyes group
Knowledge Base Contributor

Joined: 26 April 2008
Country: Netherlands
Status: Offline
Posts: 17579
Post Options Post Options   Quote MichelvA Quote  Post ReplyReply Direct Link To This Post Posted: 05 January 2009 at 09:24
Yes, the hood is ridiculous indeed. I always believed the ones on this forum who told this lens is designed with this hood, but i still wondered why some photo's were just bad.
There are 3 hoods that will fit, the Minolta 85/1.4, 20/2.8 and STF hood. I am modding yet another hood that is even better than the three mentioned. This is the hood of the Carl Zeiss 85/1.4, this one is metal (well mostly), has a padding inside and has twice the height of the std hood. There is no vignetting on APS-C. As some will know, the Zeiss lens has a bajonet with two ridges, the other mentioned have three. My mod is machining out the plastic part of the Zeiss hood and weld the inner part of the 20/2.8 hood in it.

The 28-70G with this hood is the most right one. The 17-35G (middle) std has a good metal hood with plastic bajonet.



Edited by MichelvA - 05 January 2009 at 19:28
Back to Top
Maffe View Drop Down
Moderator Group
Moderator Group

Joined: 11 November 2005
Country: Sweden
Location: Sweden
Status: Offline
Posts: 11786
Post Options Post Options   Quote Maffe Quote  Post ReplyReply Direct Link To This Post Posted: 05 January 2009 at 09:36
Using the 20/2.8 hood might be as silly on a 28-70 using aps-c.
Handy do weld the 20/2.8 fitting on th cz hood!
Back to Top
MichelvA View Drop Down
Alpha Eyes group
Alpha Eyes group
Knowledge Base Contributor

Joined: 26 April 2008
Country: Netherlands
Status: Offline
Posts: 17579
Post Options Post Options   Quote MichelvA Quote  Post ReplyReply Direct Link To This Post Posted: 05 January 2009 at 09:40
Yep, the 20/2.8 hood looks still silly. Apart from that it is still open on the sides. I am convinced the 28-70 must be shielded from any light from the side.
Back to Top
ryankburley View Drop Down
Groupie
Groupie

Joined: 15 January 2008
Country: United States
Location: Colorado
Status: Offline
Posts: 126
Post Options Post Options   Quote ryankburley Quote  Post ReplyReply Direct Link To This Post Posted: 05 January 2009 at 10:00
While most likely not what you are looking for, but I use a wide angle Lee Hood on mine when I need it. It also works great for shooting through windows as it will flex to the angle that you need to block the glare most of the time.

www.leefiltersusa.com/images/magic/LI477B75B5C2AB7-300x300.jpg

This lets me use the same hood for multiple lenses. Of course I had to get it because I use Lee's filter system.

No Vignetting at all even with the a900 and my 20mm 2.8.

I have never used the hood that came with my 28-70.
a900 / 20 F2.8 RS, 24 F2 CZ, 35 F2, 28-70 F2.8 G, 50 1.4, 85 1.4 CZ, 80-200 F2.8 HS APO G
 



Back to Top
MichelvA View Drop Down
Alpha Eyes group
Alpha Eyes group
Knowledge Base Contributor

Joined: 26 April 2008
Country: Netherlands
Status: Offline
Posts: 17579
Post Options Post Options   Quote MichelvA Quote  Post ReplyReply Direct Link To This Post Posted: 05 January 2009 at 10:05
I don't think the CZ hood will vignet on FF either as i extended the hood much further and it wasn't noticable.
Of course antoher alternative is using a 72mm hood that fits on the inner thread.
Back to Top
derettahs View Drop Down
Senior Member
Senior Member

Joined: 18 August 2008
Country: Canada
Location: Vietnam
Status: Offline
Posts: 477
Post Options Post Options   Quote derettahs Quote  Post ReplyReply Direct Link To This Post Posted: 05 January 2009 at 11:17
i have this lens as well but i have never seen the lack on contrast like in your sample shots with my version. i agree it isnt very contrasty without the hood in bright light, but i have yet to see it that bad...
and yes, the hood still sucks.
Frederik Wissink Photography

Website - www.fredwissink.com
Blog - www.fredwissink.com/blog
Back to Top
MichelvA View Drop Down
Alpha Eyes group
Alpha Eyes group
Knowledge Base Contributor

Joined: 26 April 2008
Country: Netherlands
Status: Offline
Posts: 17579
Post Options Post Options   Quote MichelvA Quote  Post ReplyReply Direct Link To This Post Posted: 05 January 2009 at 12:02
I know what you mean. I have this lens since June, 2008 and wondered why some photo's lacked contrast. It took a few weeks to connect this to the sun from the side. The photo above is the first time it was this bad, so a perfect example to make my point.
As you can see, the difference with "hood" is enormous.

Edited by MichelvA - 05 January 2009 at 19:32
Back to Top
H_K_F View Drop Down
Senior Member
Senior Member

Joined: 12 August 2005
Country: Hong Kong
Status: Offline
Posts: 1171
Post Options Post Options   Quote H_K_F Quote  Post ReplyReply Direct Link To This Post Posted: 05 January 2009 at 13:32
I had the 28-70G for years... never experienced the lack of contrast shots like yours even with the "silly" hood on the whole time... I shot panorama toward and away from the sun without such problem, there may be a green flare shot directly at the sun.

Since this lens had a "double internal flare-cutting blades" inside, external hood is basically not needed. Try attaching the lens to the camera (aperture wide-open), look at the front of the lens and rotate the zoom ring. You should see those blades in action... opening at varies degree at different focal length. If you don't see such movement, may be those blades were stuck.


Dynax 7,9,A2,5D
Sony A700,A900,A99
17-35G, 24-70Z, 28-70G, 70-200G, 35G, 50D, 85G, 100D, 300/2.8G, 600G
NEX5,5R,A7Rii
10-18, 16, 18-200, 24-70Z, 35/2.8Z, 55/1.8Z, 85/1.8Z, 70-200/4
Back to Top
MichelvA View Drop Down
Alpha Eyes group
Alpha Eyes group
Knowledge Base Contributor

Joined: 26 April 2008
Country: Netherlands
Status: Offline
Posts: 17579
Post Options Post Options   Quote MichelvA Quote  Post ReplyReply Direct Link To This Post Posted: 05 January 2009 at 13:58
The problem is that you may take 100 photo's that all look good. I noticed that only with bright sun from the side you get this effect. I did shoot directly into the sun and that went very well.
I will check the aperture tonight and let you know.
Back to Top
ab012 View Drop Down
Emeritus group
Emeritus group

Joined: 10 September 2005
Country: Australia
Status: Offline
Posts: 2675
Post Options Post Options   Quote ab012 Quote  Post ReplyReply Direct Link To This Post Posted: 05 January 2009 at 15:05
MichelvA - interesting solution, but isnt the 85ZA hood awefully expensive for a hood though
Bernard

fun fun fun
Back to Top
MichelvA View Drop Down
Alpha Eyes group
Alpha Eyes group
Knowledge Base Contributor

Joined: 26 April 2008
Country: Netherlands
Status: Offline
Posts: 17579
Post Options Post Options   Quote MichelvA Quote  Post ReplyReply Direct Link To This Post Posted: 05 January 2009 at 15:08
After you posted your message i remembered your name as you mentioned there are two aperture rings (or one aperture and one flare cutter).
Never saw this, but just checked and you're right. The ring closer to the camera seems a bit whiter (guess this is the flare cutter) and it moves beautifully and smoothly together with the aperture. I wouldn't expect other way as my 28-70 G is in an as-new condition. Wonderful construction!
Unfortunatly it doesn't prevent bad photo's, but in the 500 or so photo's i took, only 5-10 showed what you see above (edit: i must add this is the worst example, usually it is nowhere as noticable-there's just a yellow-ish coloration and lower contrast). But i still love this lens, that's why i take so much trouble to make a hood it deserves. Again: the effect only shows with light from the side, no problems at all into the sun or sun in my back.
Just a few data: i used f/4 at 70mm, ISO-400 and 1/250 s for the photo's of the monkeys.
Thanks for sharing your knowledge    

Edited by MichelvA - 05 January 2009 at 15:09
Back to Top
Bass View Drop Down
Senior Member
Senior Member

Joined: 30 January 2007
Location: United Kingdom
Status: Offline
Posts: 1308
Post Options Post Options   Quote Bass Quote  Post ReplyReply Direct Link To This Post Posted: 05 January 2009 at 16:51
I have never got the results you have without a hood, not sure why you are getting that bad a flare?

I use a collapsible rubber hood on my 28-70 with aps-c, works a treat although not the most attractive. It will vignette on Full Frame though. You can also use them with a CPL, without removing the hood which is great and really usefull.
MB
Back to Top
Dyxum main page >  Forum Home > Equipment forums > Lens Talk > A-mount lenses Page  123 9>

Forum Jump Forum Permissions View Drop Down



This page was generated in 0.078 seconds.

Monitor calibration strip

Dyxum.com - Home of the alpha system photographer

In memory of Cameron Hill - brettania

Feel free to contact us if needed.