Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
02-24-2012, 03:30 PM   #1
Veteran Member
RickyFromVegas's Avatar

Join Date: May 2011
Location: Las Vegas
Photos: Gallery
Posts: 366
MC ( Multi Coat) and its benefits?

Hello. I was just wondering about MC and its benefits on the lens.
I assumed that MC helps to resist flare and bunch, but never sought out for clarifications on that.

Another question is if an existing lens without MC treatment were to have multicoated uv filter on it, would it act as if the lens has a mc treatment?
or is that just wishful thinking?

02-24-2012, 03:32 PM   #2
Veteran Member
alohadave's Avatar

Join Date: Jan 2008
Location: Quincy, MA
Photos: Gallery | Albums
Posts: 2,024
QuoteOriginally posted by RickyFromVegas Quote
Another question is if an existing lens without MC treatment were to have multicoated uv filter on it, would it act as if the lens has a mc treatment?
or is that just wishful thinking?
Wishful thinking.
02-24-2012, 04:12 PM   #3
Veteran Member




Join Date: Mar 2010
Location: NewYork
Posts: 899
Lenses are either uncoated, single coated or multi coated. Glass reflects light. Not only will some of the light not enter the lens as it is reflected away, but every glass surface inside the lens will reflect light that will go bouncing around inside the lens. The inside of the lens is generally painted matte black to try and absorb as much as possible of this stray light. A single coated lens is the proper thickness to eliminate reflection of one wavelength of light only (one color of light only). If I understand right, the further you get from that wavelength, the more that color is reflected. They would therefor typically use a single coat tuned in the middle of the visible spectrum of light to get the most benefit. Light near the middle of the color range would get reflected the least and colors near the ends of the spectrum would get reflected the most. Multi coating uses different thickness coating that are tuned to different wavelengths, decreasing the amount of light reflected more.

If you use a multi coat filter on a lens, it may stop some reflection on the front of the lens, letting a little more light into the lens, but once in the lens (or even off the uncoated front element), the light will still get reflected off every glass element it hits.

I would imagine that the cost of disassembling a lens, cleaning and preparing the glass, and doing a custom coat job would cost much more than a new lens, if there is even any one that would do that on a single lens basis.

Edit: Seems I was wrong. You can get lenses coated. I found one reference of someone getting the glass coated in a Rolleiflex 3.5F coated which seems to have 5 or 6 small elements x 2. They stated 350$ for that. That was only for duplicating original coating on that camera though. Another mentioned 50 pounds per surface (GBP I assume?) so maybe 80$ US per surface?

A simple prime lens might have 6-10 elements (maybe more), a vivitar series 1 70-210mm has 14-15 elements (just a guess at what the average zoom has).

Figure 500$ to over 1000$ plus cost of shipping both ways to another country?

You might be able to find something cheaper, but regardless, it is obviously only economical for very expensive lenses. I think it is generally intended as an option for repair of very expensive lenses (where you might not have to do all surfaces I guess).

Last edited by ripit; 02-24-2012 at 04:36 PM.
02-24-2012, 04:25 PM   #4
Administrator
Site Webmaster
Adam's Avatar

Join Date: Sep 2006
Location: Arizona
Photos: Gallery | Albums
Posts: 40,979
All modern lenses have MC just about, but if it's an old lens (i.e. a Takumar), it might just have a single coating or no coating at all. Newer coatings are also more effective than older ones, it seems.


Adam
PentaxForums.com Webmaster (Site Usage Guide | Site Help | My Photography)



PentaxForums.com's high server and development costs are user-supported. You can help cover those costs by donating. Or, buy your photo gear from our affiliates, Adorama, B&H Photo, or Topaz Labs, and get FREE Marketplace access - click here to see how! Trusted Pentax retailers:

02-24-2012, 04:30 PM   #5
Veteran Member
RickyFromVegas's Avatar

Join Date: May 2011
Location: Las Vegas
Photos: Gallery
Posts: 366
Original Poster
The reason why I'm asking is because I have Helios 44-2 58mm.
The thing is not coated, so when shooting towards the light source, even a little bit, reflections take over a large part of the image. Was wondering if there is any way to remedy this problem a bit.

Example: one of the worst case of flare I've experienced.



The later versions of this have MC, but loses 2 blades (older has 8 blades, newer ones have 6) in the process and the bokeh looks different and more tamed, which I don't like as much.
02-24-2012, 04:35 PM   #6
Veteran Member
Laurentiu Cristofor's Avatar

Join Date: Nov 2009
Location: WA
Photos: Albums
Posts: 3,044
The main benefit of coatings is in increasing light transmission. A filter won't do any good with that. Coatings were discovered in the 30s independently in Germany and USA - read the article on wikipedia for some very interesting information. Coatings that protect against flare or ghosting were developed later - filters don't help with that either - the best they can do is to avoid introducing flare and ghosting themselves.

From a photographic perspective, however, uncoated or single coated lenses can have different rendering characteristics and might be desirable because of that. Helios 44 lenses, for example, have gained sharpness as they gained multicoatings, but their bokeh is allegedly different.
02-24-2012, 04:38 PM   #7
Veteran Member
rparmar's Avatar

Join Date: Jan 2008
Photos: Gallery
Posts: 8,783
QuoteOriginally posted by RickyFromVegas Quote
Another question is if an existing lens without MC treatment were to have multicoated uv filter on it, would it act as if the lens has a mc treatment?
or is that just wishful thinking?
Adding a filter adds a new gas layer and a new glass layer, neither of which were taken into account by the lens designer. This provides more surfaces for spurious reflections, scratches, dust, etc. and more possibilities of degradation.

I never use filters for "protection". Use a lens hood instead.

If you have a lens without MC that is subject to flare, shoot in situations that avoid this problem. Or get a longer hood. Or use your hand for shade. As a photographer, you can outwit your gear. ;-)
02-24-2012, 04:39 PM   #8
Veteran Member
Laurentiu Cristofor's Avatar

Join Date: Nov 2009
Location: WA
Photos: Albums
Posts: 3,044
QuoteOriginally posted by RickyFromVegas Quote
The thing is not coated, so when shooting towards the light source, even a little bit, reflections take over a large part of the image. Was wondering if there is any way to remedy this problem a bit.
Yes, follow religiously Rule #1 of using Russian lenses: Don't shoot into the light! Keep the sun in the back!

I started photography with a Russian rangefinder and I still position myself with the back to the sun when I'm about to photograph something - I don't even think about it.

02-24-2012, 07:18 PM   #9
Veteran Member
hcarvalhoalves's Avatar

Join Date: Aug 2010
Location: São Paulo, Brazil
Posts: 836
QuoteOriginally posted by RickyFromVegas Quote
The reason why I'm asking is because I have Helios 44-2 58mm.
The thing is not coated, so when shooting towards the light source, even a little bit, reflections take over a large part of the image. Was wondering if there is any way to remedy this problem a bit.

Example: one of the worst case of flare I've experienced.



The later versions of this have MC, but loses 2 blades (older has 8 blades, newer ones have 6) in the process and the bokeh looks different and more tamed, which I don't like as much.
I have the same lens, but probably a newer, multi-coated version. It doesn't flare that bad even shooting right into the sun:


IMGP2460 - Version 2 por hcarvalhoalves, no Flickr
02-24-2012, 07:26 PM - 1 Like   #10
Veteran Member
hcarvalhoalves's Avatar

Join Date: Aug 2010
Location: São Paulo, Brazil
Posts: 836
BTW, here's an interesting video showing some pretty simple lenses being made. From 1:55 and on you can see their coating process.


Last edited by hcarvalhoalves; 02-24-2012 at 07:33 PM.
02-25-2012, 02:56 AM - 1 Like   #11
Senior Member
simbon4o's Avatar

Join Date: Jan 2011
Photos: Gallery | Albums
Posts: 258
Тhere are coatings and coatings, try the M 50 1.7 against the sun there is no GDR glass that can match!
02-25-2012, 03:08 AM   #12
Veteran Member
RickyFromVegas's Avatar

Join Date: May 2011
Location: Las Vegas
Photos: Gallery
Posts: 366
Original Poster
I have FA-A-M 50mm f1.4-f1.7-f2.
A50mm1.7 being my fav.
02-25-2012, 11:25 AM   #13
Veteran Member
Laurentiu Cristofor's Avatar

Join Date: Nov 2009
Location: WA
Photos: Albums
Posts: 3,044
QuoteOriginally posted by hcarvalhoalves Quote
I have the same lens, but probably a newer, multi-coated version. It doesn't flare that bad even shooting right into the sun:
Ahhh! Multicoated windows!
02-25-2012, 02:14 PM   #14
Veteran Member
kcobain1992's Avatar

Join Date: Dec 2010
Location: Bucharest, Romania
Photos: Gallery
Posts: 1,409
QuoteOriginally posted by RickyFromVegas Quote
The reason why I'm asking is because I have Helios 44-2 58mm.
The thing is not coated, so when shooting towards the light source, even a little bit, reflections take over a large part of the image. Was wondering if there is any way to remedy this problem a bit.

Example: one of the worst case of flare I've experienced.



The later versions of this have MC, but loses 2 blades (older has 8 blades, newer ones have 6) in the process and the bokeh looks different and more tamed, which I don't like as much.
The solution is called lens hood, and avoid shooting into the sun. Look for a 49mm diameter, and get the longest one you can get (for telephoto, doesn't matter, the longer the better).
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
k-mount, lens, mc, pentax lens, slr lens, treatment
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Getting a K5 benefits my granddaughter! PALADIN85020 Pentax K-5 4 05-24-2011 04:32 AM
Matte of gloss coat? dj_saunter Digital Processing, Software, and Printing 9 03-11-2011 09:18 AM
For Sale - Sold: B+W 49mm UV HAZE Filter MRC 010M F-Pro Multi Coat (US) pcarfan Sold Items 0 12-14-2010 06:47 PM
WR - more than weather benefits? pacerr Pentax SLR Lens Discussion 4 12-03-2010 07:19 PM
Super Coat? NecroticSoldier Pentax SLR Lens Discussion 6 04-06-2010 04:46 PM



All times are GMT -7. The time now is 10:57 AM. | See also: NikonForums.com, part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top