What is the DC to spot a ruby carried by a gremlin, from 50 feet away?

Question

What would be the DC to spot a ruby on a gremlin from 50 feet away, assuming optimal lighting and environmental conditions? Let's say he was just holding in his hand, and the ruby is about a Grade 4 (so about golf ball size?).

I set it at 10 plus 5 for distance = 15, and two PCs successfully spotted it. I'm OK with that outcome of that spot ruling, but I'd like to do it more correctly next time.

I suppose it was a Grade 4 gemstone. http://paizo.com/pathfinderRPG/prd/ultimateEquipment/appendix.html

Answer 1

The base DC to spot a creature that's out in the open is 0, and I think it's safe to say the same is true of objects. There's a penalty of -1 to the check for every 10 feet between the observer and the target. In your case, 50 feet, so -5 (or effectively, DC +5).

A creature using Stealth would benefit from a size modifier, but the ruby isn't hiding, nor is the gremlin attempting to conceal it. So your total DC should be 5. If you want it to be higher, the gremlin should have concealed it.

Answer 2

The Perception check DC to spot the ruby would be:

• 0: Detect a visible creature

• +5: target is 50 feet away (+1 per 10 feet)

• -2: target is in a bright light condition and you must notice something reflective it is carrying on one of it's hands.

1 Favorable and unfavorable conditions depend upon the sense being used to make the check. For example, bright light might decrease the DC of checks involving sight, while torchlight or moonlight might increase the DC. Background noise might increase a DC involving hearing, while competing odors might increase the DC of a check involving scent.

• Total: DC 3

Yes, it's not difficult to notice that he has a ruby on his hands, but someone might fail. It's those things you mention when describing the encounter: You see a small creature, greenish, with long pointy ears and battered leather and fur clothes, it holds a small blade, maybe a dagger, on one hand and a red gem on the other.

If you look at the tables for Vision on the Exploration and Movement rules, it says:

Bright Light

In an area of bright light, all characters can see clearly. Some creatures, such as those with light sensitivity and light blindness, take penalties while in areas of bright light. A creature can't use Stealth in an area of bright light unless it is invisible or has cover. Areas of bright light include outside in direct sunshine and inside the area of a daylight spell.

Bright light is created by direct sunlight, as well as by spells such as daylight.

Color and detail are easily determined by most creatures in bright light, though shiny or reflective surfaces can be difficult to look at.

It is impossible for characters in bright light to attempt Stealth checks without cover or invisibility.

However, this is to notice a gem that is open for everyone to see, if this gremlin is holding it in his hands and it's difficult to see, you can apply some Stealth Modifiers to increase this DC. Do note that this is not RAW and merely subject to my interpretation of the situation. But to explain why im applying this modifier, it is applied to a stealth check regardless of the skill ranks or the ability of the creature performing it, so even if it rolls a 1 on the d20, it still grants that bonus. Thus we can treat that as a passive bonus that can be applied to perception checks.

To notice the gremlin would be a DC 7 check (3 + 4 for a small creature), easily done with a take 10 check. To notice the small gem on his clasped hands would be a DC 19 (3 + 16 for a fine object), hardly easy unless this character is focused on perception. But it's not impossible either even for lv1 characters.

In general, you shouldn't use Perception checks for something that is simple to spot. If you want to make a check, you need some factor to make it tricky and harder to spot.