117 — Noise Halos and Chromatic Aberration — Interview with Royce Howland

On the Rocks, Moraine Lake by Royce How­land — An HDR exam­ple where Royce con­trolled the set­tings to make sure no halos appeared in the sky or water.

Fall at Abra­ham Lake by Royce How­land — Another HDR exam­ple where Royce left the halo­ing in the sky, and in fact accen­tu­ated it a bit more via a Pho­to­shop Curves adjust­ment, to give a sense of glow over the moun­tains. So some­times halos are not a flaw, they’re a cre­ative choice.

Loom­ing, Abra­ham Lake by Royce How­land — An HDR exam­ple involv­ing a high con­trast back­lit scene. The trees were deeply shad­owed. Even on a Pen­tax 645D medium for­mat cam­era, there’s noise in those trees in a nor­mal sin­gle expo­sure. Bot­tom left — A 100% crop of a sin­gle expo­sure that went into the image above show­ing the level of noise in the trees. Bot­tom right — A 100% crop of the final image. Using a com­bi­na­tion of HDR tech­nique and a touch of addi­tional noise reduc­tion, I was able to sub­tly boost the con­trast in the deep shad­ows, pre­serve all of the gen­uine detail, and also vir­tu­ally elim­i­nate the dig­i­tal noise. With­out HDR tech­nique, just using a noise reduc­tion fil­ter can take the dig­i­tal noise down but gen­er­ally also will sac­ri­fice legit­i­mate detail as well.

Ghost Of Server Present, Jerome by Royce How­land — An indoor shot taken with avail­able light in some­what dim con­di­tions at a sup­pos­edly haunted hotel. I’m using a bunch of cre­ative tech­niques here includ­ing shal­low depth of field, a reflec­tion in a mir­ror, sub­ject motion blur and extra dig­i­tal blur­ring. Despite the soft­en­ing effects of all the tech­niques used in this image, I also wanted a bit of tex­ture and bit of “vin­tage film grain” feel. So far from remov­ing all dig­i­tal noise, I actu­ally con­trolled it and then added a uni­form mono­chro­matic grain layer on top of every­thing in Pho­to­shop. In print up to 16x20 size it’s dif­fi­cult to see this grain, but on a nice matte paper it gives a slight feel­ing of tex­ture; whereas run­ning noise reduc­tion as I would nor­mally do in fact makes the results look­ing flat and plas­tic. You can see the noise detail added in the bot­tom detailed part of the image.

Chro­matic aber­ra­tion exam­ple at f/3.5 by Royce How­land — It was a bit after noon so the sun was high, and I shot straight into the light. The tree branches against a darker back­ground show extremely high con­trast edges. I was using a Sony RX100 pocket cam­era, which is a very high qual­ity point & shoot with a Carl Zeiss lens. So a qual­ity piece of kit for a com­pact. The first com­po­si­tion was at medium lens zoom and the aper­ture wide open — f/3.5. Bot­tom left — A 100% crop of the shot shows a lot of green and pur­ple fringes are vis­i­ble along the branch edges. Even towards the cen­ter of the lens, the chro­matic aber­ra­tion is pretty bad. This is a file con­verted from RAW using the lat­est Adobe Cam­era Raw in Pho­to­shop CS6, no chro­matic aber­ra­tion removal. Bot­tom right — Now here’s the iden­ti­cal file, but using the green and pur­ple fringe removal set­tings dur­ing RAW con­ver­sion. Quite strong set­tings were needed for the green fringes, not so strong for pur­ple. Mostly the fringes were removed.

Chro­matic aber­ra­tion exam­ple at f/5.6 by Royce How­land — Now here is the same com­po­si­tion pho­tographed again moments later in the same strong light, but stop­ping the lens down to f/5.6. Bot­tom left — Stop­ping the lens down just over 1 stop has actu­ally got­ten rid of many of the pur­ple & green fringes with­out doing any­thing else. That’s because a slightly smaller aper­ture lets through less of the mis­aligned light rays that con­tribute to the chro­matic aber­ra­tion in the first place. This is a RAW file con­verted again with no chro­matic aber­ra­tion set­tings. Bot­tom right — And here’s the same file con­verted with a small amount of pur­ple and green defringe set­tings, much less than needed in the first exam­ple and the results look better.